Hope you had a great time New Year and now you are in a great holiday mood. At least that’s how it is for me - we didn’t drink any alcohol, and at midnight we clinked glasses of water from a five-liter canister, so we woke up, took a walk, and then I remembered one of yesterday’s New Year greetings:
I wish that at the end of each year, remembering what happened over the past 366 if ((year%4 == 0 and year%100 != 0) or (year%400 == 0)) else 365 days, think about myself:Oh, nifiga yourself, what an action was. I will definitely tell my grandchildren or write a book about it later.
For example, 2013 is a common year, 1700, 1800 and 1900 are again common years, but 2000, 2004, 2008 and 2012 are leap years.
But what if we don't remember how many days there are in leap years (366 days) and common years (365 days), or we just want to write the definition of the number of days in a year as quickly as possible? Is it possible to do this in Python? Of course you can.
So, Python has a calendar module. It is just great for finding out if a particular year is a leap year (or, for example, how many leap years are in a certain interval), determining the number of days in a month, getting the number of the day of the week for certain date and so on.
In particular, we can get the number of days in each month of the year, and simply add them up.
The calendar.monthrange function takes the year number as the first argument and the month number as the second argument. Returns the number of the day of the week on the first day of the given month and the number of days in the given month:
>>> import calendar >>> calendar.monthrange(2013, 1) (1, 31)
Accordingly, we can calculate the total number of days for all 12 months, and thus obtain the number of days for a given year:
>>> import calendar >>> year = 2013 >>> sum(map(lambda x: calendar.monthrange(year, x), range(1, 13))) 365
But if you think about how exactly this line is executed, it becomes obvious that this solution is very inefficient if you need to calculate the number of days for a large number years.
We check with the timeit module.
To complete it 1 million times, it takes 13.69 seconds if import calendar is done once at the beginning. If import calendar is done every time then 14.49 seconds.
Now let's try another option. It requires knowing how many days there are in leap and non-leap years, but it is very short:
>>> import calendar >>> year = 2013 >>> 365+calendar.isleap(year) 365
And, as you might guess, it is already much faster: 0.83
seconds, including import calendar, and 0.26
seconds if import calendar is done once at the beginning.
Let's also see how long the very first option takes, with a "manual" approach: 0.07 seconds for 2012 and 2013 and 0.12 seconds for 2000 (I think everyone understands where such a difference in speed for these years comes from).
It turns out that this is the fastest option out of these three:
>>> import calendar >>> year = 2013 >>> 366 if ((year%4 == 0 and year%100 != 0) or (year%400 == 0)) else 365 365
Of course, in most cases, you can use either of these options - after all, when determining the number of days in one, two, ten, or a hundred years, you are unlikely to feel any difference.
Write, optimize, improve, test and evaluate performance - but don't forget about the readability of your program sources.
Happy New Year! Good luck, happiness, joy and self-improvement in the new year.
In the Julian and Gregorian calendars, a leap year is a year that consists of 366 days. Thus, it differs from the usual one by the presence of an “extra” day. In the Julian calendar, every fourth year is a leap year. As for the Gregorian, it has a similar approach to determining a leap year, but with a small exception.
To be considered a leap year, the year must first of all be divisible by four. Regarding zero years, from which centuries begin, they are considered leap years only if their number is a multiple of 400. So, for example, the year 2000 is a leap year, while the year 1900 is not.
As for the question of how many days are in a leap year, the world's most widely used Gregorian calendar contains 366 days. The “extra” day is February 29th. Thus, people born on this day officially celebrate their birthday every four years. This interesting feature leap years.
Our planet is constantly revolving around its celestial body - the Sun. The Earth makes a complete revolution in 365 days and several hours. This period of time is called a "year". For convenience of calculation, the “extra” few hours are not taken into account for three years. In the fourth year, additional hours are added up and, as a result, an “extra” day is obtained, which is usually added to every fourth February.
Given the above rules for determining leap years, it is possible to form a list of them for the last centuries. So, in the XIX century, these were: 1804, 1808, 1812, 1816, 1820, 1824, 1828, 1832, 1836, 1840, 1844, 1848, 1852, 1856, 1860, 1864, 1868, 1872, 187 6, 1880, 1884, 1888, 1892, 1896.
In the 20th century, leap years were respectively 1904, 1908, 1912, 1916, 1920, 1924, 1928, 1932, 1936, 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 19 72, 1976, 1980, 1984 , 1988, 1992, 1996.
As for the 21st century, in which we all were lucky enough to live, the leap years were 2000, 2004, 2008, 2012. The next leap year will be 2016.
Despite the fact that the origin and features of leap years have long been studied and absolutely clear, many people are apprehensively waiting for their onset. It so happened that leap year considered something strange and somewhere even dangerous. Nevertheless, if we analyze history, in ordinary years there were no less various kinds of cataclysms and negative events than in leap years. Therefore, it is not necessary to attach any special significance to leap years.
All life on Earth is determined by the proximity to the Sun and the movement of the planet around it and around its own axis. A year is the time during which our planet flies around the Sun, and a day is the time for a complete revolution around its axis. Of course, it is very convenient for people to plan their affairs by weeks, to count a certain number of days in a month or a year.
But it turns out that for a complete revolution around the Sun, the Earth rotates around its axis not the full number of times. That is, there is not a full number of days in a year. Everyone knows that this happens 365 times and this corresponds. In fact, a little more: 365, 25, that is, an extra 6 hours accumulate in a year, and to be completely accurate, an extra 5 hours, 48 minutes and 14 seconds.
Naturally, if this time is not taken into account, then the hours will add up to a day, those to months, and in a few hundred years the difference between the generally accepted and astronomical calendar will be several months. For social life, this is completely unacceptable: all holidays and memorable dates will be moved.
Such difficulties were discovered quite a long time ago, even under one of the greatest of them - Gaius Julius Caesar.
Emperors in Ancient Rome were revered on a par with the gods, had unlimited power, so they just remade the calendar with one order, and that's it.
In ancient Rome, the whole year was based on the celebration of calends, non and ides (as the parts of the month were called). In this case, February was considered the last. Thus, in a leap year, there are 366 days, and extra night have been in the last month.
After all, it was quite logical to add a day in the last month of the year, in February. And, interestingly, not the last day was added, as it is now, but an additional day before the calendars of the month of March. Thus, in February there were two twenty-fourths. Leap years were appointed after three years, and the first of them happened already during the life of Caesar Gaius Julius. After his death, the system got a little off, because the priests made a mistake in the calculations, but over time correct calendar leap years recovered.
Now leap years are considered a bit more complicated. And this is due to those few extra minutes that are obtained by introducing a full extra day every four years.
The Gregorian calendar, according to which secular society currently lives, was introduced by Pope Gregory at the end of the 16th century. The reason it was introduced new calendar, lies in the fact that the previous timing was inaccurate. By adding a day every four years, the Roman ruler did not take into account that in this way the official calendar would be ahead of the generally accepted one by 11 minutes and 46 seconds every four years.
At the time of the introduction of the new calendar, the inaccuracy of the Julian was 10 days, over time it has increased and is now 14 days. The difference increases every century by about a day. It is especially noticeable on a summer day and winter solstice. And since some holidays are counted from these dates, the difference was noticed.
The Gregorian leap year calendar is a bit more complex than the Julian calendar.
The Gregorian calendar takes into account the difference in the official and astronomical calendar of 5 hours, 48 minutes and 14 seconds, that is, every 100 years one leap year is canceled.
So how do you know which year is a leap year and which is not? Is there a system and algorithm for canceling an extra day? Or is it better to use
For convenience, such an algorithm is actually introduced. In general, every fourth year is considered a leap year, for convenience, years that are multiples of four are used. Therefore, if you need to find out whether the year of your grandmother's birth or the start of World War II was a leap year, you just need to find out whether this year is divisible by 4 or not. Thus, 1904 is a leap year, 1908 is also a leap year, but 1917 is not.
A leap year is canceled when the century changes, that is, in a year that is a multiple of 100. Thus, 1900 was not a leap year because it is a multiple of 100, common years are also 1800 and 1700. But an extra day does not accumulate in a century, but in about 123 years, that is, again it is necessary to make amendments. How do you know which year is a leap year? If a year is a multiple of 100 and a multiple of 400, it is considered a leap year. That is, 2000 was a leap year, just like 1600.
The Gregorian calendar, with such complex amendments, is so accurate that there is extra time, but we are talking about seconds. Such seconds are also called leap seconds, so that it is immediately clear what it is about. There are two of them a year and they are added on June 30 and December 31 at 23:59:59. These two seconds equalize astronomical and universal time.
A leap year is one day longer than usual, it has 366 days. Earlier, back in Roman times, this year there were two days on February 24, but now, of course, the dates are counted differently. This year in February there is one more day than usual, that is 29.
But it is believed that the years in which there is February 29 are unlucky. There is a belief that in leap years the death rate rises, various misfortunes occur.
If you look at the mortality diagram in the USSR in the second half of the 20th century and in Russia, you can see that the most high level noted in 2000. This can be explained by economic crises, low living standards and other problems. Yes, 2,000 was a leap year (since it's divisible by 400), but is that the rule? 1996 is by no means a record holder in terms of mortality; in 1995, which preceded it, the mortality was higher.
This indicator reached its minimum mark in almost half a century in non-leap years, but in 1986 the mortality rate was also low, much lower than, for example, in 1981.
Many more examples can be cited, but it is already clearly seen that mortality does not increase in “long” years.
If you look at the birth rate statistics, then you can’t find a clear relationship with the length of the year either. Leap years of the 20th century did not confirm the theory of misfortune. The birth rate both in Russia and in European countries is falling evenly. A slight rise is observed only in 1987, and then the birth rate begins to grow steadily after 2008.
Maybe the leap year determines some tension in politics or predetermines natural disasters or wars?
Among the dates of the beginning of hostilities, you can find only one leap year: 1812 - the war with Napoleon. For Russia, it ended quite happily, but, of course, it was a serious test in itself. But neither the year of the revolution of 1905 nor 1917 was a leap year. The year the Second World War began (1939) was certainly the most unfortunate year for all of Europe, but it was not a leap year.
In leap years, an explosion also occurred, but events such as Chernobyl disaster, the tragedy in the Japanese cities of Hiroshima and Nagasaki, volcanic eruptions and other disasters happened in the most ordinary years. The list of leap years in the 20th century does not at all coincide with the mournful list of misfortunes and catastrophes.
Psychologists believe that all statements about the fatality of a leap year are nothing more than superstition. If it is confirmed, they talk about it. And if it is not confirmed, they simply forget about it. But the expectation of misfortune in itself can “pull” trouble. It is not for nothing that often happens to a person exactly what he is afraid of.
One of the saints said: "If you do not believe in omens, they will not be fulfilled." IN this case this is more than welcome.
The traditional Jewish calendar uses lunar months, which are 28 days long. As a result, the calendar year according to this system lags behind the astronomical one by 11 days. An additional month in the year is regularly introduced for adjustment. A leap year in the traditional Jewish calendar consists of thirteen months.
Leap years for Jews are more common: out of nineteen years, only twelve are common, and another seven are leap years. That is, the Jews have much more leap years than in the usual case. But, of course, we are talking only about the traditional Jewish calendar, and not about the one according to which the modern state of Israel lives.
All our contemporaries will no longer face exceptions in the calculation of leap years. The next year, which will not be a leap year, is expected only in 2100, this is hardly relevant for us. So the next leap year can be calculated very simply: the nearest year that is divisible by 4.
2012 was a leap year, 2016 will also be a leap year, 2020 and 2024, 2028 and 2032 will be leap years. It is quite easy to calculate this. Of course, it is necessary to know this, but do not let this information scare you. And in a leap year, wonderful and joyful events happen. For example, people born on February 29 are considered lucky and happy.
Everyone has heard of the existence of a leap year. But few people know where this name came from, and how humanity has a certain time limit in reserve, which in the future may be a whole year. Why leap years of the 21st century are considered unlucky, how they can be determined - will be described in this review.
The common unit of time is the year.
During this period of time, a full seasonal cycle takes place:
It is during this period of time that the Earth makes a complete revolution around the star Sun. This action takes 365 full days and 6 hours. This time period is called the astronomical year. One day contains 24 hours. Of the "extra" 6 hours of each year, an additional day is accumulated, falling on every fourth year in a row. This day falls on February 29th.
Important! The presence of the 29th day in February makes the year a leap year.
The unusual year owes its name to the Latin language, from which literally “Bicsextus” is translated as “second sixth”. In the Julian calendar, the “extra” number was the second 24. And since February was the last month of the year according to the Caesar calendar, an extra day was added to it.
Since the beginning of world history, mankind has become aware of two types of calendars:
Starting from January 1, 45 BC, civilized mankind lived according to the Julian calendar, which Gaius Julius Caesar founded. According to this calendar, every third year was followed by a long year with a 366-day composition.
The Romans believed that it takes 365.25 days for a complete revolution of the planet around the heavenly body, while the exact date is 365 days 5 hours 48 minutes 46 seconds. It turns out that every year between the two equinoxes there is a difference of 11 minutes and 14 seconds.
Thus, over 128 years of these minutes, one day has accumulated, and over 16 centuries this figure has increased to 10. In the Julian calendar, a leap year was any that was a multiple of 100, 200.
This continued until 1582, when Pope Gregory, then acting at that time, introduced a new calendar, where a leap year is not only every fourth year, but even one that is a multiple of 400. Such, for example, was 2000.
One of the reasons why it was decided to change the calendar was the Christian holidays, which were required to be celebrated at a certain time without shifting. So, the Catholic Pope Gregory XIII proposed his own calendar, which was approved and adopted during the Ecumenical Council.
Answering the question of how to determine a leap year without having a table at hand, every second even year of the Gregorian calendar should be considered as such.
Since 1918, the inhabitants of our country began to use the Gregorian calendar. Since the transition to the Gregorian style, dates have been mixed by 10 days, although until now, the difference between the Gregorian and Julian calendars increases by 3 days every four centuries.
In order to know for sure and not wonder how to determine a leap year, you need to adopt such a feature - the number of the year is divisible by 4, 100 and 400 without a trace. If the number is divisible by 4,100 but not divisible by 400, then the year is not a leap year. Taking into account this information, you can easily determine the desired year.
It must be admitted that if we did not have leap years, there would be a regular shift of the seasons. Therefore, they help to synchronize the Gregorian and astrological calendars, and not allow the seasons to shift to other months.
But why a leap year is considered bad, you should understand. In Slavic culture, there has long been a negative attitude towards such years. An extra day in February was considered the cause of disasters and dashing deeds.
Perhaps the reason for such dislike was the fact that this time of February 29, according to Slavic beliefs, is subject to Kashchei-Chernobog, who commanded dark forces, sowing evil, death, disease and madness.
Often, the ancient Russians associated a leap day with Cassian, who was born just on February 29th. Based on the legends, where he was assigned the role of a guardian of the gates of Hell, a traitor cherub, a pupil of demons, etc., one can understand why this character was greatly feared and strongly cursed. The Russians were sure that Cassian had a negative impact on the whole year. There was a pestilence of cattle and poultry, crops were destroyed in the fields, and famine set in.
On the day of February 29, the people tried once again not to go out into the yard, to keep cattle and poultry locked up.
It is difficult to unequivocally answer why a leap year is considered bad. Some scientists claim that natural disasters and man-made disasters are becoming more frequent during this period of time. Many individuals are also in a hurry to write off their individual troubles for more than a year.
Historical facts are such tragic events:
This list can be continued for a long time. These are the statistics that back up most of the popular beliefs, superstitions and signs.
Good to know! Those newlyweds who dared to celebrate their wedding in a leap year were predicted to have a difficult family life.
In order to plan important events in your life, such as marriage, the birth of children, a change of profession, place of residence, etc., information about which leap years this century will be useful.
Leap years, list in the 20th century: 1904, 1908, 1912, 1916, 1920, 1924, 1928, 1932, 1936, 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, 1980, 1984 1988, 1992, 1996.
Leap years in our century: 2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036, 2040, 2044, 2048, 2052, 2056, 2060, 2064, 2068, 207 2, 2076, 2080, 2084, 2088, 2092, 2096, 2100.
It is generally accepted that all years since February 29 bring trouble and are marked by tragic events. But, taking into account the information received, we can conclude that you should not pay too much attention to signs. Bad events and cataclysms happened at different times.
Some people, on the contrary, endow the leap year with mystical properties, and wonder why it is considered bad.
Certain lucky ones and originals consider themselves to be people born on February 29th. They can celebrate their birthday only once every 4 years.
Positive attitude and faith in own forces constitute a powerful base for important accomplishments in a person's life, and small superstitions should not become an obstacle to achieving goals.
The main difference between a leap year is the number of days in February. In a leap year, unlike a normal year, February has twenty-nine days instead of the usual twenty-eight. There are different opinions as to whether a leap year can be called unlucky. Superstitious people are afraid of its onset, because they associate with it the beginning of a difficult period in life. This year, a person in all matters is accompanied by failures that cannot be avoided. But this is just one of the opinions.
Leap year is not just popularly considered bad. An old legend is associated with it, which reveals the history of the origin of this year.
The leap year is associated with the name of the angel Kasyan. The Lord trusted him with his plans and thoughts. But Kasyan could not resist the temptation and went over to the side dark forces. He was punished for his betrayal. For three years he was beaten for his anger and cowardice, and in the fourth year he descended to the ground and harmed people in every possible way. Our ancestors believed that Kasyan could ruin their crops and bring diseases to livestock.
It cannot be unequivocally stated that a leap year is unlucky. Yes, there are more accidents all over the world. But this is explained quite simply: the statistics of incidents increase due to the fact that the leap year is one day longer. This is a logical explanation that is difficult to dispute. The number of months does not change, but one is added for the day during which an accident, car accident or death of a person can occur.
Why does a girl dream - interpretation of dream books
Many examples related to leap years have come down to us. The most controversial of them is the sign that a marriage entered into this year will not be happy for the young. This superstition didn't just happen. He has his own history. In ancient times, the leap year was called the "Year of brides." The girl could choose her betrothed and woo him. According to the rules, the groom could not refuse, even if he was in love with another girl. Marriages were not based on mutual love. Because of this, the relationship was not happy and strong. Therefore, there was a prejudice that this year it is undesirable to hold a wedding.
In Orthodoxy, this sign is skeptical. The wedding must take place church calendar, to which leap year has nothing to do. For Muslims, this year is not bad. There are no superstitions and superstitions in Islam.
People born in a leap year were ambiguously perceived by our ancestors. Someone believed that a baby had an unhappy fate from childhood. There is an opposite opinion, according to which the child is unique, different from other children. Happy awaits him successful life, in all endeavors he will be lucky.
People believed that a child whose birthday is February 29 is endowed with esoteric abilities. He was born for a reason, on earth he has a good and bright mission: to help others.
The Signs of Destiny cannot be ignored. If a person feels that he is endowed with a rare gift, he should use it for good purposes.
There are many prohibitions that relate to people's lives. They all come down to the fact that you should not make big plans for a leap year. There is a high probability that they will not be implemented. What to avoid:
