Wikipedia:Reference desk/Archives/Computing/2017 April 23

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April 23[edit]

Review for Macbook Pro 15" mid-2015 integrated graphics[edit]

I'm trying to find a review for the mid-2015 Macbook Pro with Intel Iris graphics. I'm specifically interested in its battery life. To clarify, there are two separate models of the mid-2015 15" Macbook Pro:

Model 1: Macbook Pro 15" mid-2015 with AMD graphics [1]

Model 2: Macbook Pro 15" mid-2015 with Intel Iris graphics [2]

Model 1 has thousands upon thousands of reviews on the internet[3][4][5][6][7][8][9][10][11][12], most of them done by reputable sources. Model 2 has no review on the web, as far as I can find. Which is strange because model 1 has been discontinued, while model 2 has not. Model 2 also had better sales compared to model 1 (as reflected by the fact that it's still being manufactured).

I'm specifically interested in the battery life difference between the two models. All I could find are forum posts[13][14] positing that the integrated graphics models has better life, but with no evidence to back it up. A review that contains a proper battery life test should clear that right up. ECS LIVA Z (talk) 04:30, 23 April 2017 (UTC)[reply]

Using Arduino without using it[edit]

Once we have written and compiled/uploaded a sketch successfully to the Arduino, (supposing it works with 2 or 3 steeper motors and a gyroscope chip attached to particular terminals of Arduino), is it possible to remove Arduino alltogther and upload the successfully compiled program to some small chip especially designed to take place of Arduino, so this self-created gadget (with an appropriate battery ) can be of portable use without wasting the Arduino itself? 2405:205:4000:9A2B:0:0:12B7:80A0 (talk) 09:30, 23 April 2017 (UTC)[reply]

An Arduino board is basically a way of making it easy to do prototyping. A straightforward commercial implementation would simply put the circuit consisting of the processor and some other devices from the Arduino board together with the ones on the prototype breadboard on a small printed circuit board. Dmcq (talk) 13:32, 23 April 2017 (UTC)[reply]
Yes! Absolutely. Most of the arduino is just a prototyping board.
The tricky part is that the ATMEGA chips in an Arduino come pre-loaded with the arduino bootloader software, so if you just pop a blank chip into an arduino it's not going to work.
There are many ways to get the bootloader on an blank chip. This is probably the cheapest if you already have some Arduinos laying around, but the proper programmers aren't expensive. [15] And there's plenty of instructions[16] on how to use them. ApLundell (talk) 15:08, 23 April 2017 (UTC)[reply]
Or you can skip all that and pay a couple extra bucks to buy chips with the Arduino software loaded and ready to go.[17]. ApLundell (talk) 15:11, 23 April 2017 (UTC)[reply]
You need to be able to sell a few tens of thousands before considering anything much cheaper than is talked about here. The next step up is to produce something on a tiny board like in those small black blobs inside toys.
  • "What is an Arduino?" is actually quite a hard question to answer. The minimal generic 'duino is an AVR chip with a copy of the open-source Arduino bootloader burned into its memory, thus allowing compiled Arduino sketches to be downloaded to it. You can make this yourself from raw chips and a larger board (as part of some embedded system), or by attaching an outsourced Arduino as a daughter board. Commercial products make all of these routes cheap and easy: you can buy the AVR chips (in several sizes, both logical and physical), you can buy AVRs with a factory-loaded Arduino bootloader, or you can buy a Mini 'duino as a small board with pins more cheaply (literally "a couple of bucks") than I can have the chips assembled for me, and far more simply than having to assemble a board with a small quad pack CPU on it. I can also (and have done) burn my own bootloaders with a programmer costing a couple of $10, but it's tiresome to do this.
Another option is to abandon writing Arduino sketches and write directly for the AVR chip. It's not hard to program this, the skillset transfers pretty easily. If you're doing realtime, muti-threading or especially interrupts, then it's easier than making an Arduino sketch achieve the same. One you've done this, you can burn that directly to the chip and avoid needing a bootloader at all.
This month, the embedded Mini Arduino board is much the favourite option of these. Andy Dingley (talk) 11:44, 24 April 2017 (UTC)[reply]
Oh yes definitely. If you're not doing more than a thousand there's no point even thinking about making your own board at this price level. Dmcq (talk) 12:35, 24 April 2017 (UTC)[reply]

How do I change a list of numbers to a specific number in notepad++?[edit]

How do I change a list of numbers to a specific number in notepad++?

As some example changing all the numbers between -1 and -32768 (including -1 and -32768) to -32768 201.79.59.205 (talk) 17:42, 23 April 2017 (UTC)[reply]

You'd probably want to use -\d+ instead, since the version with the asterisk will match a single dash even if it's not followed by a number. Also, depending on the contents of the document, you might want to enhance the regular expression to avoid matching, for example, the last 5 characters of a phone number like 555-1212 or a date like 4-24-2017. This would be easy if the desired negative numbers are always preceded by a space or some other recognizable character. CodeTalker (talk) 14:29, 24 April 2017 (UTC)[reply]
  • Tigraan, today, I tried to solve a problem using regular expressions. It worked perfectly the first time. Now I'm sitting here confused and terrified to actually implement that solution because I have no idea how to deal with that. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 16:39, 24 April 2017 (UTC)[reply]