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What's the difference between echo, print, and print_r in PHP?
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print and echo are more or less the same; they are both language constructs that display strings. The differences are subtle: print has a return value of 1 so it can be used in expressions whereas echo has a void return type; echo can take multi...
How to print last two columns using awk
...of variable NF which is set to the total number of fields in the input record:
awk '{print $(NF-1),"\t",$NF}' file
this assumes that you have at least 2 fields.
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php is null or empty?
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What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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Python: try statement in a single line
...variables to something. If they might not get set, set them to None first (or 0 or '' or something if it is more applicable.)
If you do assign all the names you are interested in first, you do have options.
The best option is an if statement.
c = None
b = [1, 2]
if c is None:
a = b
else:...
IF… OR IF… in a windows batch file
Is there a way to write an IF OR IF conditional statement in a windows batch-file?
14 Answers
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PUT vs. POST in REST
According to the HTTP/1.1 Spec:
34 Answers
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How to extract a floating number from a string [duplicate]
... I say floating and not decimal as it's sometimes whole. Can RegEx do this or is there a better way?
7 Answers
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What exactly is a C pointer if not a memory address?
In a reputable source about C, the following information is given after discussing the & operator:
25 Answers
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Find the max of two or more columns with pandas
...a dataframe with columns A , B . I need to create a column C such that for every record / row:
2 Answers
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static allocation in java - heap, stack and permanent generation
I have been lately reading a lot on memory allocation schemes in java, and there have been many doubts as I have been reading from various sources. I have collected my concepts, and I would request to go through all of the points and comment on them. I came to know that memory allocation is JVM spec...