integer

问题 I am working with huge numbers for website purposes and I need long calculation. When I echo a long number I don't get the correct output. Example // A random number $x = 100000000000000000000000000; $x = number_format($x); echo "The number is: $x <br>"; // Result: 100,000,000,000,000,004,764,729,344 // I'm not getting the value assigned to $x 回答1: Your number is actually too big for php standard integers. php uses 64 bit integers which can hold values within range -9223372036854775808 ( PHP

问题 How do I print out the index location of each of a python list so that it starts at 1, rather than 0. Here's an idea of what I want it to look like: blob = ["a", "b", "c", "d", "e", "f"] for i in blob: print(???) Output: 1 a 2 b 3 c 4 d 5 e What I need to know is how do I get those numbers to show up alongside what I'm trying to print out? I can get a-e printed out no problem, but I can't figure out how to number the list. 回答1: for a, b in enumerate(blob, 1): print '{} {}'.format(a, b) 回答2:

问题 I'm encountering a problem with incorrect numpy calculations when the inputs to a calculation are a numpy array with a 32-bit integer data type, but the outputs include larger numbers that require 64-bit representation. Here's a minimal working example: arr = np.ones(5, dtype=int) * (2**24 + 300) # arr.dtype defaults to 'int32' # Following comment from @hpaulj I changed the first line, which was originally: # arr = np.zeros(5, dtype=int) # arr[:] = 2**24 + 300 single_value_calc = 2**8 * (2*

问题 How to convert float to integer in prolog? I tried: ?- integer(truncate(sqrt(9))). false. ?- integer(round(sqrt(9))). false. 回答1: The predicate integer/1 that you used is true iff its argument is an integer. Since the term truncate(sqrt(9)) is not an integer, the predicate does not hold and therefore fails for this term. There are at least two ways to get what you want: Solution 1: Quick and broken You can use the predicate (is)/2 for conversion between different number representations. In

问题 I have binary strings in the form of either: <<"5.7778345">> or <<"444555">> I do not know before hand whether it will be a float or integer. I tried doing a check to see if it is an integer. Does not work since it is binary. And tried converting binary to list then check if int or float. Not much success with that. It needs to be a function such as binToNumber(Bin) -> %%Find if int or float Return. Anyone have a good idea of how to do this? All the Best 回答1: No quick way to do it. Use

问题 I need to check the value of the least significant bit (LSB) and most significant bit (MSB) of an integer in C/C++. How would I do this? 回答1: //int value; int LSB = value & 1; Alternatively (which is not theoretically portable, but practically it is - see Steve's comment) //int value; int LSB = value % 2; Details: The second formula is simpler. The % operator is the remainder operator. A number's LSB is 1 iff it is an odd number and 0 otherwise. So we check the remainder of dividing with 2.

问题 Why are Python integers implemented as objects? The article Why Python is Slow: Looking Under the Hood as well as its comments contain useful information about the Python memory model and its ramifications, in particular wrt to performance. But this article does not ask or answer the question why the decision to implement integers as objects was made in the first place. In particular, referring to Python as dynamically typed is not an answer. It is possible to implement integers as integers

问题 Why are Python integers implemented as objects? The article Why Python is Slow: Looking Under the Hood as well as its comments contain useful information about the Python memory model and its ramifications, in particular wrt to performance. But this article does not ask or answer the question why the decision to implement integers as objects was made in the first place. In particular, referring to Python as dynamically typed is not an answer. It is possible to implement integers as integers

问题 I have a data frame that has years in it (data type chr ): Years: 5 yrs 10 yrs 20 yrs 4 yrs I want to keep only the integers to get a data frame like this (data type num ): Years: 5 10 20 4 How do I do this in R? 回答1: you need to extract the numbers and treat them as type numeric df$year <- as.numeric(sub(" yrs", "", df$year)) 回答2: Per your additional requirements a more general purpose solution but it has limits too. The nice thing about the more complicated years3 solution is it deals more

问题 I have a data frame that has years in it (data type chr ): Years: 5 yrs 10 yrs 20 yrs 4 yrs I want to keep only the integers to get a data frame like this (data type num ): Years: 5 10 20 4 How do I do this in R? 回答1: you need to extract the numbers and treat them as type numeric df$year <- as.numeric(sub(" yrs", "", df$year)) 回答2: Per your additional requirements a more general purpose solution but it has limits too. The nice thing about the more complicated years3 solution is it deals more