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SQL NVARCHAR and VARCHAR Limits
...sult will be typed as nvarchar(max).
nvarchar(max) + varchar(n) will first convert the varchar(n) input to nvarchar(n) and then do the concatenation. If the length of the varchar(n) string is greater than 4,000 characters the cast will be to nvarchar(4000) and truncation will occur.
Datatypes of s...
How do I print a double value with full precision using cout?
...limits<double>::digits10 + 2) because 2 extra digits are needed when converting from decimal back to the binary representation to ensure the value is rounded to the same original value. Here is a paper with some details: docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
...
How to create empty data frame with column names specified in R? [duplicate]
...
why does z convert to Factor?
– pssguy
Jul 21 '13 at 19:29
6
...
When should I use Struct vs. OpenStruct?
... = 2;
Here are some common use cases.
OpenStructs can be used to easily convert hashes to one-off objects which respond to all the hash keys.
h = { a: 1, b: 2 }
o = OpenStruct.new(h)
o.a = 1
o.b = 2
Structs can be useful for shorthand class definitions.
class MyClass < Struct.new(:a,:b,:c)...
Objective-C formatting string for boolean?
...
One way to do it is to convert to strings (since there are only two possibilities, it isn't hard):
NSLog(@" %s", BOOL_VAL ? "true" : "false");
I don't think there is a format specifier for boolean values.
...
How to output something in PowerShell
...
Objects also don't get blindly converted to string, but pass through a formatter which decides on what to do with them. That's why you see Get-ChildItem's output coming in a table form, for example, and results with many properties (e.g. WMI) default to Fo...
What are bitwise shift (bit-shift) operators and how do they work?
...d together makes 320:
(row * 320) = (row * 256) + (row * 64)
Now we can convert that into left shifts:
(row * 320) = (row << 8) + (row << 6)
For a final result of:
memoryOffset = ((row << 8) + (row << 6)) + column
Now we get the same offset as before, except instead ...
Why not use java.util.logging?
...o I would think that a massive library written in 2002 with log4j could be converted to JUL in a matter of minutes with an automated tool. (I don't know if one exist, though). So why doesn't it happen?
– peterh
Jul 6 '12 at 9:49
...
Summarizing multiple columns with dplyr? [duplicate]
...le(1:5, 10, replace=T),
grp = sample(1:3, 10, replace=T))
# Convert to tidy format using gather
df %>%
gather(key = variable, value = value, a:d) %>%
group_by(grp, variable) %>%
summarize(mean = mean(value)) %>%
spread(variable, mean)
#> Source: local da...
How to measure time in milliseconds using ANSI C?
...y, so if you have a ticks value and the frequency is known, you can easily convert ticks to elapsed time. It is actually not guaranteed that a monotonic clock reflects the current system time in any way, it may also count ticks since a system startup. But it guarantees that a clock is always run up ...