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Change one value based on another value in pandas

...ere. Assuming you can load your data directly into pandas with pandas.read_csv then the following code might be helpful for you. import pandas df = pandas.read_csv("test.csv") df.loc[df.ID == 103, 'FirstName'] = "Matt" df.loc[df.ID == 103, 'LastName'] = "Jones" As mentioned in the comments, you ...
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Block Declaration Syntax List

...at this is distinct from "Blocks as Parameters"; in this instance, you're calling a method that wants a block argument with an anonymous block. If you have already declared a block variable, it is sufficient to pass the variable name as the argument. [someObject doSomethingWithBlock: ^return_type (...
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SQL WHERE.. IN clause multiple columns

... or more generally SELECT * FROM table INNER JOIN otherTable ON ( table.x = otherTable.a AND table.y = otherTable.b) – ala Jul 16 '09 at 7:56 ...
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Would you, at present date, use JBoss or Glassfish (or another) as Java EE server for a new project?

...ce them otherwise? If so, there's your answer. Do I have to use EJBs? Really? Avoid them if at all possible--they are really only needed for very large, enterprise-class systems. Remember that they are merely tools, and big ones at that (can anyone say "Golden Sledgehammer"?). They are heavily...
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Is there a JavaScript / jQuery DOM change listener?

Essentially I want to have a script execute when the contents of a DIV change. Since the scripts are separate (content script in the Chrome extension & webpage script), I need a way simply observe changes in DOM state. I could set up polling but that seems sloppy. ...
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How would you count occurrences of a string (actually a char) within a string?

...nsion methods on the string class. I guess they figured devs wouldn't want all those extension methods to show up on the string class. Probably a wise decision. – Judah Gabriel Himango Feb 15 '09 at 23:27 ...
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this.setState isn't merging states as I would expect

...construct a new state and then call setState() on that: var newSelected = _.extend({}, this.state.selected); newSelected.name = 'Barfoo'; this.setState({ selected: newSelected }); I've used function _.extend() function (from underscore.js library) here to prevent modification to the existing sele...
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Why do x86-64 systems have only a 48 bit virtual address space?

... Because that's all that's needed. 48 bits give you an address space of 256 terabyte. That's a lot. You're not going to see a system which needs more than that any time soon. So CPU manufacturers took a shortcut. They use an instruction set...
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Create an array with random values

... var random_array = new Array(40).fill().map((a, i) => a = i).sort(() => Math.random() - 0.5); I think this does the same as above – Jamie337nichols Sep 16 '19 at 18:47 ...
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Why doesn't print work in a lambda?

...ed print function if you are using the latest Python 2.x: In [1324]: from __future__ import print_function In [1325]: f = lambda x: print(x) In [1326]: f("HI") HI share | improve this answer ...