units-of-measurement

问题 I'm developing a Web application using F#. Thinking of protecting user input strings from SQL, XSS, and other vulnerabilities. In two words, I need some compile-time constraints that would allow me discriminate plain strings from those representing SQL, URL, XSS, XHTML, etc. Many languages have it, e.g. Ruby’s native string-interpolation feature #{...} . With F#, it seems that Units of Measure do very well, but they are only available for numeric types. There are several solutions employing

问题 How do I know which is the default measure system (imperial or metric) on iOS ? How do I get this preference from the device settings, so I know what to display in my app ? thanks 回答1: The NSLocale can tell you: NSLocale *locale = [NSLocale currentLocale]; BOOL isMetric = [[locale objectForKey:NSLocaleUsesMetricSystem] boolValue]; Only three countries do not use the metric system: the US, Liberia and Myanmar. The later uses its own system, the former two use Imperial Units. Apples

问题 Does setWidth(int pixels) use device independent pixel or physical pixel as unit? For example, does setWidth(100) set the a view's width to 100 dips or 100 pxs? Thanks. 回答1: It uses pixels, but I'm sure you're wondering how to use dips instead. The answer is in TypedValue.applyDimension(). Here's an example of how to convert dips to px in code: // Converts 14 dip into its equivalent px Resources r = getResources(); int px = Math.round(TypedValue.applyDimension( TypedValue.COMPLEX_UNIT_DIP, 14

问题 I'm trying to make an app that displays something in real-world units. It's not a ruler app, but it wants that kind of precision. It already looks like the iPhone and iPod touch have different screen resolutions (160 & 163 respectively) I've found this Calculating pixel size on an iPhone and this iPhone screen resolution changes in future hardware and this http://forums.macrumors.com/showthread.php?t=350612 From my reading it sounds like I can treat the 320 * 480 screen space as 2 * 3.5

问题 I'm using the great quantities package for Python. I would like to know how I can get at just the numerical value of the quantity, without the unit. I.e., if I have E = 5.3*quantities.joule I would like to get at just the 5.3. I know I can simply divide by the "undesired" unit, but hoping there was a better way to do this. 回答1: E.item() seems to be what you want, if you want a Python float. E.magnitude , offered by tzaman, is a 0-dimensional NumPy array with the value, if you'd prefer that.

问题 I was wondering if anyone could help me create a function that will turn millimeters into feet/inches. Example: 5280mm will be returned as 17ft / 3.87inches (or 17'3") I know that there's 304.8mm in a foot, which gives me 17.322834645669 (using the same example above) but I'm not sure how to then format it into something more legible. function getMeasurements($mm) { return ($mm/304.8); } 回答1: And if anyone is looking to do the same thing, this is what I used to calculate mm to ft/inches:

问题 Are there in the literature some standard scalability measures for distributed systems ? I'm searching in google (and also google scholar) but I came up with only few papers (e.g., https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=862209). In particular, I was wondering if there are some scalability measures for the three axes of the AKF cube or cube of the scalability (http://microservices.io/articles/scalecube.html), which is described in the book The Art of Scalability, by Abbott

问题 I have strings containing numbers with their units, e.g. 2GB, 17ft, etc. I would like to separate the number from the unit and create 2 different strings. Sometimes, there is a whitespace between them (e.g. 2 GB) and it's easy to do it using split(' '). When they are together (e.g. 2GB), I would test every character until I find a letter, instead of a number. s='17GB' number='' unit='' for c in s: if c.isdigit(): number+=c else: unit+=c Is there a better way to do it? Thanks 回答1: s='17GB' for

问题 Short version: I have a dataframe with two columns: Latitude and Longitude, being each of them in degrees, minutes and seconds. After reading some similar questions like this one, I decided to use measurements package to make the conversion, but results get messed when converting from one unit to another (see below). Detailed version: Provided the following dataframe where I have two columns, Latitude and Longitude expressed in degrees, minutes and seconds df = data.frame( Latitude = c("15°

问题 I am working on a LAMP web application which is managing a lot of data with different measurement units. This php application use a custom MVC framework. We now have customers in different countries and we would like to offer the choice to the customer between metric, imperial or combination. Currently, all the data are saved in international unit in our MySQL database. Some tables have multiple columns containing data with different units. What would be the best DB architecture to manage the