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How to write to an existing excel file without overwriting data (using pandas)?
...omething like this might work out:
import pandas
from openpyxl import load_workbook
book = load_workbook('Masterfile.xlsx')
writer = pandas.ExcelWriter('Masterfile.xlsx', engine='openpyxl')
writer.book = book
## ExcelWriter for some reason uses writer.sheets to access the sheet.
## If you leave ...
How to define two fields “unique” as couple
...
There is a simple solution for you called unique_together which does exactly what you want.
For example:
class MyModel(models.Model):
field1 = models.CharField(max_length=50)
field2 = models.CharField(max_length=50)
class Meta:
unique_together = ('field1', 'fi...
How to work around the lack of transactions in MongoDB?
...iewpoint (I have only worked with SQL databases so far), or whether it actually can't be done.
10 Answers
...
How to run an EXE file in PowerShell with parameters with spaces and quotes
...mand starting with a string it just evaluates the string, that is, it typically echos it to the screen, for example:
PS> "Hello World"
Hello World
If you want PowerShell to interpret the string as a command name then use the call operator (&) like so:
PS> & 'C:\Program Files\IIS\Mi...
Hidden features of Ruby
...
From Ruby 1.9 Proc#=== is an alias to Proc#call, which means Proc objects can be used in case statements like so:
def multiple_of(factor)
Proc.new{|product| product.modulo(factor).zero?}
end
case number
when multiple_of(3)
puts "Multiple of 3"
when multiple...
Is there a numpy builtin to reject outliers from a list
...ng like the following? That is, take a list d and return a list filtered_d with any outlying elements removed based on some assumed distribution of the points in d .
...
When should I make explicit use of the `this` pointer?
...
Usually, you do not have to, this-> is implied.
Sometimes, there is a name ambiguity, where it can be used to disambiguate class members and local variables. However, here is a completely different case where this-> is e...
How do I get an ISO 8601 date on iOS?
...
Use NSDateFormatter:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
NSLocale *enUSPOSIXLocale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
[dateFormatter setLocale:enUSPOSIXLocale];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ssZZZZZ"];
[dateFormatter setCale...
Split comma-separated strings in a column into separate rows
...solution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the microbenchmark package (see code below).
The sample data given by the OP consists only of 20 rows. To create larger data frames, these 20...
Rails 4 - passing variable to partial
...buyer } %>
<%= render "account", account: @buyer %>
# @account.to_partial_path returns 'accounts/account', so it can be used to replace:
# <%= render partial: "accounts/account", locals: { account: @account} %>
<%= render @account %>
# @posts is an array of Post instances, so ...