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Which is better, number(x) or parseFloat(x)?
..., I find Number to be more reasonable, so I almost always use Number personally (and you'll find that a lot of the internal JavaScript functions use Number as well). If someone types '1x' I prefer to show an error rather than treat it as if they had typed '1'. The only time I really make an exceptio...
What is ANSI format?
...ghtly generic term used to refer to the standard code page on a system, usually Windows. It is more properly referred to as Windows-1252 on Western/U.S. systems. (It can represent certain other Windows code pages on other systems.) This is essentially an extension of the ASCII character set in that ...
Difference between .keystore file and .jks file
...y. Some application use a keystore file stored in $HOME/.keystore: it's usually implied that it's a JKS file, since JKS is the default keystore type in the Sun/Oracle Java security provider. Not everyone uses the .jks extension for JKS files, because it's implied as the default. I'd recommend using ...
How to access pandas groupby dataframe by key
...df_list = map(lambda df_i: grouped.get_group(df_i), sampled_df_i)
optionally - turn it all back into a single dataframe object
sampled_df = pd.concat(df_list, axis=0, join='outer')
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impr...
What does %s mean in a python format string?
...insert values into a
string with the %s placeholder.
Edit: Here is a really simple example:
#Python2
name = raw_input("who are you? ")
print "hello %s" % (name,)
#Python3+
name = input("who are you? ")
print("hello %s" % (name,))
The %s token allows me to insert (and potentially format) a st...
Creating an array of objects in Java
...is:
A a1;
A a2;
A a3;
A a4;
Now you couldn't do a1.someMethod() without allocating a1 like this:
a1 = new A();
Similarly, with the array you need to do this:
a[0] = new A();
...before using it.
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Why is “a” != “a” in C?
...ifferent strings, which are stored in different locations. Doing so essentially looks like this:
if(0x00403064 == 0x002D316A) // Two memory locations
{
printf("Yes, equal");
}
Use the following code to compare two string values:
#include <string.h>
...
if(strcmp("a", "a") == 0)
{
...
What's the difference of ContentType and MimeType
... What's the main difference between the
each one, and when is right to call
something mimetype as opposed to
content-type ? Am i being pitty and
grammar nazi?
The reason isn't only backward compatibility, and I'm afraid the usually excellent Django documentation is a bit hand-wavy about i...
Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...<- data.frame(a = 1:3, b = letters[1:3])
comparison <- compare(a1,a2,allowAll=TRUE)
comparison$tM
# a b
#1 1 a
#2 2 b
#3 3 c
The function compare gives you a lot of flexibility in terms of what kind of comparisons are allowed (e.g. changing order of elements of each vector, changing order a...
Escape single quote character for use in an SQLite query
...
for replace all (') in your string, use
.replace(/\'/g,"''")
example:
sample = "St. Mary's and St. John's";
escapedSample = sample.replace(/\'/g,"''")
sha...