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Javascript what is property in hasOwnProperty?
...n has been edited so it's now being called on an object. When it's not, an error is thrown.
– James Allardice
Feb 22 '12 at 14:31
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How to get a random value from dictionary in python
...'walk': 20, 'run': 80} and when I use random.choice(a.keys()), there is an error like "dict_keys' object does not support indexing". Do you know what's wrong? Thanks a lot!!!
– beepretty
May 11 '16 at 4:50
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Cannot use object of type stdClass as array?
I get a strange error using json_decode() . It decode correctly the data (I saw it using print_r ), but when I try to access to info inside the array I get:
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Is System.nanoTime() completely useless?
... int status = gettimeofday(&time, NULL);
assert(status != -1, "linux error");
return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
}
jlong os::javaTimeNanos() {
if (Linux::supports_monotonic_clock()) {
struct timespec tp;
int status = Linux::clock_gettime(CLOCK_MONOTO...
Detect application heap size in Android
...ication heap size available":
How much heap can my app use before a hard error is triggered? And
How much heap should my app use, given the constraints of the Android OS version and hardware of the user's device?
There is a different method for determining each of the above.
For item 1 above: ...
memory_get_peak_usage() with “real usage”
...031 MiB
real: 1 MiB
not real: 0.97883605957031 MiB
real: 1 MiB
PHP Fatal error: Allowed memory size of 1048576 bytes exhausted (tried to allocate 793601 bytes) in /home/niko/test.php on line 7
Seems like real usage is the memory allocated from the system - which seems to get allocated in larger...
How to check if a float value is a whole number
...
For older versions, the naive implementation of that function (skipping error checking and ignoring infinity and NaN) as mentioned in PEP485:
def isclose(a, b, rel_tol=1e-9, abs_tol=0.0):
return abs(a - b) <= max(rel_tol * max(abs(a), abs(b)), abs_tol)
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How do you create a dictionary in Java? [closed]
...", "value");
String value = dictionary.get("key");
Works but gives an error you need to keep the constructor class same as the declaration class. I know it inherits from the parent class but, unfortunately it gives an error on runtime.
Map<String, String> dictionary = new Map<String,...
How to validate an email address in JavaScript
... reject any valid addresses [^@]+@[^@]+\.[^@]+ and protects against common errors.
– Vroo
Oct 26 '12 at 6:32
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Alter a MySQL column to be AUTO_INCREMENT
...CREMENT after the fact. I have tried the following SQL, but got a syntax error notification.
19 Answers
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