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Read Excel File in Python
...ues for a given column
values = df['Arm_id'].values
#get a data frame with selected columns
FORMAT = ['Arm_id', 'DSPName', 'Pincode']
df_selected = df[FORMAT]
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Getting the first character of a string with $str[0]
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Yes. Strings can be seen as character arrays, and the way to access a position of an array is to use the [] operator. Usually there's no problem at all in using $str[0] (and I'm pretty sure is much faster than the substr() method).
There is only one ca...
Error in strings.xml file in Android
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post your complete string. Though, my guess is there is an apostrophe (') character in your string. replace it with (\') and it will fix the issue. for example,
//strings.xml
<string name="terms">
Hey Mr. Android, are you stuck? Here, I\'ll clear a path for you.
</string>
Ref:
ht...
What's the difference between a word and byte?
...s “Addressable unit of data large enough to hold any member of the basic character set of the execution environment.”
What this means is that the byte consists of at least enough adjacent bits to accommodate the basic character set for the implementation. That is, the number of possible values ...
How does Stack Overflow generate its SEO-friendly URLs?
...ength;
bool prevdash = false;
var sb = new StringBuilder(len);
char c;
for (int i = 0; i < len; i++)
{
c = title[i];
if ((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9'))
{
sb.Append(c);
prevdash = fa...
Error “initializer element is not constant” when trying to initialize variable with const
...s_pFooInit = (&(const foo_t){ .a=2, .b=4, .c=6 });
int main (int argc, char **argv) {
const foo_t *const f1 = &s_FooInit;
const foo_t *const f2 = s_pFooInit;
printf("Foo1 = %d, %d, %d\n", f1->a, f1->b, f1->c);
printf("Foo2 = %d, %d, %d\n", f2->a, f2->b, f2->...
Why does sizeof(x++) not increment x?
...at is initialized as a quoted string, instead of using strlen(), where the character array comprising the string has to be scanned for the null-terminator at run time, sizeof(quoted_string) is known at compile time, and therefore at run-time. It's a small thing, but if you use the quoted string in a...
Why is “while ( !feof (file) )” always wrong?
...e is again std::cin, just as before.
POSIX, write(2) to flush a buffer:
char const * p = buf;
ssize_t n = bufsize;
for (ssize_t k = bufsize; (k = write(fd, p, n)) > 0; p += k, n -= k) {}
if (n != 0) { /* error, failed to write complete buffer */ }
The result we use here is k, the numb...
google mock分享（全网最全最好的gmock文档，没有之一） - C/C++ - 清泛网 ...
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using namespace std;
using ::testing::Return;
int main(int argc, char** argv) {
::testing::InitGoogleMock(&argc, argv);
string value = "Hello World!";
MockFoo mockFoo;
EXPECT_CALL(mockFoo, getArbitraryString()).Times(1).
WillOnce(Retu...
Why historically do people use 255 not 256 for database field magnitudes?
You often see database fields set to have a magnitude of 255 characters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
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