For your first code, you can use a short alteration of the answer given by @ShankarDamodaran using in_array(): if ( !in_array($some_variable, array(‘uk’,’in’), true ) ) { or even shorter with [] notation available since php 5.4 as pointed out by @Forty in the comments if ( !in_array($some_variable, [‘uk’,’in’], true ) ) { is the same … Read more
Using: df[ (df.A==’blue’) & (df.B==’red’) & (df.C==’square’) ][‘D’] = ‘succeed’ gives the warning: /usr/local/lib/python2.7/dist-packages/ipykernel_launcher.py:2: SettingWithCopyWarning: A value is trying to be set on a copy of a slice from a DataFrame. Try using .loc[row_indexer,col_indexer] = value instead A better way of achieving this seems to be: df.loc[(df[‘A’] == ‘blue’) & (df[‘B’] == ‘red’) & (df[‘C’] … Read more
It’s also a common practice when people are building the sql query programmatically, it’s just easier to start with ‘where 1=1 ‘ and then appending ‘ and customer.id=:custId’ depending if a customer id is provided. So you can always append the next part of the query starting with ‘and …’.
Think of ! (negation operator) as “not”, || (boolean-or operator) as “or” and && (boolean-and operator) as “and”. See Operators and Operator Precedence. Thus: if(!(a || b)) { // means neither a nor b } However, using De Morgan’s Law, it could be written as: if(!a && !b) { // is not a and is … Read more
Poor man’s solution: volumes: ${VARIABLE:-/dev/null}:/app/folder Or: volumes: ${VARIABLE:-/dev/null}:${VARIABLE:-/tmp}/app/folder
The short answer is the operator needs to be at the end of the line in order to tell Ruby to continue reading the next line as part of the statement, so this would work: if ( (aa != nil && self.prop1 == aa.decrypt) || (bb != nil && self.prop2 == bb.decrypt) ) && (self.id.nil? … Read more
Summarising my initial post and comments – there are several advantages of switch statement over if/else statement: Cleaner code. Code with multiple chained if/else if … looks messy and is difficult to maintain – switch gives cleaner structure. Performance. For dense case values compiler generates jump table, for sparse – binary search or series of … Read more
There are some resources on the Anti-IF Campaign site, such as this article. I believe it’s a matter of degree. Conditionals aren’t always bad, but they can be (and frequently are) abused. Additional thoughts (one day later) Refactoring: Improving the Design of Existing Code is a good reference on this subject (and many others). It … Read more
In most browsers (not IE <= 8) arrays have a filter method, which doesn’t do quite what you want but does create you an array of elements of the original array that satisfy a certain condition: function isGreaterThanFive(x) { return x > 5; } [1, 10, 4, 6].filter(isGreaterThanFive); // Returns [10, 6] Mozilla Developer Network … Read more