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How to compare two floating point numbers in Bash?
...niently
This can be done more conveniently using Bash's numeric context:
if (( $(echo "$num1 > $num2" |bc -l) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
En...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...
See the C FAQ, Question 1.32
Q: What is the difference between these initializations?
char a[] = "string literal";
char *p = "string literal";
My program crashes if I try to assign a new value to p[i].
A: A string literal (the formal term
for a double-quot...
java.lang.IllegalStateException: Cannot (forward | sendRedirect | create session) after response has
...gnoring the remnant of the code. For example:
protected void doXxx() {
if (someCondition) {
sendRedirect();
}
forward(); // This is STILL invoked when someCondition is true!
}
This is thus actually not true. They do certainly not behave differently than any other Java methods (e...
How to use int.TryParse with nullable int? [duplicate]
I am trying to use TryParse to find if the string value is an integer. If the value is an integer then skip foreach loop. Here is my code.
...
NUnit Test Run Order
...Your unit tests should each be able to run independently and stand alone. If they satisfy this criterion then the order does not matter.
There are occasions however where you will want to run certain tests first. A typical example is in a Continuous Integration situation where some tests are long...
When should I use Write-Error vs. Throw? Terminating vs. non-terminating errors
...
Write-Error should be used if you want to inform the user of a non-critical error. By default all it does is print an error message in red text on the console. It does not stop a pipeline or a loop from continuing. Throw on the other hand produces what...
How do I test for an empty JavaScript object?
... keys).
Pre-ECMA 5:
function isEmpty(obj) {
for(var prop in obj) {
if(obj.hasOwnProperty(prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
jQuery:
jQuery.isEmptyObject({}); // true
lodash:
_.isEmpty({}); // true
Underscore:
_.isEmpty({});...
How to get the nth occurrence in a string?
...
I would have been good if you specified what each parameter meant.
– Foreever
Jun 10 '14 at 8:49
1
...
Simple state machine example in C#?
...on(CurrentState, command);
ProcessState nextState;
if (!transitions.TryGetValue(transition, out nextState))
throw new Exception("Invalid transition: " + CurrentState + " -> " + command);
return nextState;
}
public ProcessState M...
How to create a MySQL hierarchical recursive query
...cte
on p.parent_id = cte.id
)
select * from cte;
The value specified in parent_id = 19 should be set to the id of the parent you want to select all the descendants of.
MySQL 5.x
For MySQL versions that do not support Common Table Expressions (up to version 5.7), you would achieve this ...