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How to resolve “must be an instance of string, string given” prior to PHP 7?
...Prior to PHP 7 type hinting can only be used to force the types of objects and arrays. Scalar types are not type-hintable. In this case an object of the class string is expected, but you're giving it a (scalar) string. The error message may be funny, but it's not supposed to work to begin with. Give...
Assign pandas dataframe column dtypes
...you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x ...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
Performance associated with Arrays and Objects in JavaScript (especially Google V8) would be very interesting to document. I find no comprehensive article on this topic anywhere on the Internet.
...
Save classifier to disk in scikit-learn
How do I save a trained Naive Bayes classifier to disk and use it to predict data?
6 Answers
...
Get Image size WITHOUT loading image into memory
I understand that you can get the image size using PIL in the following fashion
6 Answers
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Is there a way to detect if an image is blurry?
...
Yes, it is. Compute the Fast Fourier Transform and analyse the result. The Fourier transform tells you which frequencies are present in the image. If there is a low amount of high frequencies, then the image is blurry.
Defining the terms 'low' and 'high' is up to you.
E...
Code Golf: Collatz Conjecture
...
x86 assembly, 1337 characters
;
; To assemble and link this program, just run:
;
; >> $ nasm -f elf collatz.asm && gcc -o collatz collatz.o
;
; You can then enjoy its output by passing a number to it on the command line:
;
; >> $ ./collatz 123
; >&...
Does C have a “foreach” loop construct?
... \
for(T * item = list->head; item != NULL; item = item->next)
And can be used like
for_each_item(i, processes) {
i->wakeup();
}
Iteration over an array is also possible:
#define foreach(item, array) \
for(int keep = 1, \
count = 0,\
size = sizeof (...
Append integer to beginning of list in Python [duplicate]
I have an integer and a list. I would like to make a new list of them beginning with the variable and ending with the list.
Writing a + list I get errors. The compiler handles a as integer, thus I cannot use append, or extend either.
How would you do this?
...
Can I change the checkbox size using CSS?
...oz-transform: scale(2); /* FF */
-webkit-transform: scale(2); /* Safari and Chrome */
-o-transform: scale(2); /* Opera */
transform: scale(2);
padding: 10px;
}
/* Might want to wrap a span around your checkbox text */
.checkboxtext
{
/* Checkbox text */
font-size: 110%;
di...