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How do I filter ForeignKey choices in a Django ModelForm?
...tions = super(FrontEndAdmin, self).get_actions(request)
if 'delete_selected' in actions:
del actions['delete_selected']
return actions
prevents delete permission
def has_delete_permission(self, request, obj=None):
return False
filters objects that can be ...
Make a float only show two decimal places
...
IN objective-c, if you are dealing with regular char arrays (instead of pointers to NSString) you could also use:
printf("%.02f", your_float_var);
OTOH, if what you want is to store that value on a char array you could use:
sprintf(your_char_ptr, "%.02f", your_float_va...
Hash function that produces short hashes?
...ay of encryption that can take a string of any length and produce a sub-10-character hash? I want to produce reasonably unique ID's but based on message contents, rather than randomly.
...
How to prevent gcc optimizing some statements in C?
...ore by using the volatile type qualifier.
// Assuming pageptr is unsigned char * already...
unsigned char *pageptr = ...;
((unsigned char volatile *)pageptr)[0] = pageptr[0];
The volatile type qualifier instructs the compiler to be strict about memory stores and loads. One purpose of volatile is...
Can a C++ enum class have methods?
... mouse_event_middle_up,
mouse_event_wheel
};
static const char* ToStr (const type::LowLevelMouseEvent::Enum& event)
{
switch (event) {
case mouse_event_unknown: return "unknown";
case mouse_event_unimplemented: return "unimplemented"...
C compile error: “Variable-sized object may not be initialized”
...
This gives error:
int len;
scanf("%d",&len);
char str[len]="";
This also gives error:
int len=5;
char str[len]="";
But this works fine:
int len=5;
char str[len]; //so the problem lies with assignment not declaration
You need to put value in the following way:
s...
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
......
}
}
const_cast :
// *Passwd declared as a const
const unsigned char *Passwd
// on some situation it require to remove its constness
const_cast<unsigned char*>(Passwd)
reinterpret_cast :
typedef unsigned short uint16;
// Read Bytes returns that 2 bytes got read.
bool ByteBu...
Generic TryParse
... answered Jul 1 '11 at 22:11
Charlie BrownCharlie Brown
79755 silver badges22 bronze badges
...
What would be the Unicode character for big bullet in the middle of the character?
... These links contain some more info like HTML entities for these four characters: fileformat.info/info/unicode/char/25cf fileformat.info/info/unicode/char/26ab fileformat.info/info/unicode/char/2b24 fileformat.info/info/unicode/char/1f311
– D Coetzee
Aug 3...
What is the difference between join and merge in Pandas?
...ral methods to deal with these situations, among them merge, join, append, concat, combine, combine_first. Take a look at each of these to have a glimpse about which one would be the best fit for your situation
– xiaxio
Mar 29 at 19:03
...