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What is the best way to test for an empty string in Go?

... Both styles are used within the Go's standard libraries. if len(s) > 0 { ... } can be found in the strconv package: http://golang.org/src/pkg/strconv/atoi.go if s != "" { ... } can be found in the encoding/json package: http://golang.org/src/pkg/encoding/...
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Differences between numpy.random and random.random in Python

.... I inspired myself in other people's code so I ended up using the numpy.random module for some things (for example for creating an array of random numbers taken from a binomial distribution) and in other places I use the module random.random . ...
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Computed read-only property vs function in Swift

...operties for just that: properties; meaning simple values that you can get and/or set. I use functions (or methods) when actual work is being done. Maybe something has to be computed or read from disk or from a database: In this case I use a function, even when only a simple value is returned. That ...
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Drop columns whose name contains a specific string from pandas DataFrame

I have a pandas dataframe with the following column names: 10 Answers 10 ...
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TimePicker Dialog from clicking EditText

...( "" + selectedHour + ":" + selectedMinute); Your missing a + between "" and selected hour, setText methods only take a single string, so you need to concatenate all the parts (the first quotes are likely unnecessary). eReminderTime.setOnClickListener(new OnClickListener() { @Override ...
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Logical operators (“and”, “or”) in DOS batch

... You can do and with nested conditions: if %age% geq 2 ( if %age% leq 12 ( set class=child ) ) or: if %age% geq 2 if %age% leq 12 set class=child You can do or with a separate variable: set res=F if %hour% leq 6 se...
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How to check if command line tools is installed

...as it appears in the Applications directory. There are also the xcodebuild and xcode-select files in /usr/bin I need to know if the command line tools is installed. Is there a command for it? What can I do to see if XCode CLT is installed and if yes to find the version installed? ...
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Dynamically select data frame columns using $ and a character value

I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
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Evaluate expression given as a string

...ied. For example, if you have a pre-defined variable name equal to "David" and you reassign using eval(parse(text = "name") == "Alexander", you will get an error because eval & parse do not return an R expression that can be evaluated. – Crt Aug 1 '16 at 22...
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How to select option in drop down using Capybara

... can be: id, name, related label element. You can read more about Capybara and DSL options here. – Nesha Zoric Feb 26 '18 at 12:37 add a comment  |  ...