The line-height is determined by dividing the targeted line-height size by the font-size. In this example, Bootstrap is baselining their line-height off of a 14px font-size. The target line-height is 20px:

**20px &#247; 14px = 1.428571429**

When determining your line-height, you want to make sure you have ample white space between your rows. This allows for ascenders and descenders without intruding on other rows. Also having ample white space allows your eyes to develop a visual rhythm while reading.

Also keeping the line-height unitless makes it more versatile. For more information, [see Eric Meyer&#39;s post on this from February 2006.](http://meyerweb.com/eric/thoughts/2006/02/08/unitless-line-heights/)

I have a list that countain values, one of the values I got is &#39;nan&#39;

    countries= [nan, &#39;USA&#39;, &#39;UK&#39;, &#39;France&#39;]

I tried to remove it, but I everytime get an error 

    cleanedList = [x for x in countries if (math.isnan(x) == True)]
    TypeError: a float is required

When I tried this one : 

    cleanedList = cities[np.logical_not(np.isnan(countries))]
    cleanedList = cities[~np.isnan(countries)]
    
    TypeError: ufunc &#39;isnan&#39; not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule &#39;&#39;safe&#39;&#39;

How can I remove Nan from list Python/NumPy

In my emulator, when I try to do an upgrade of my apk programmatically. I get:

`Android App Not Install. `

`An existing package by the same name with a conflicting signature is already installed`

![enter image description here][1]

I&#39;m still in the testing phase of this upgrade, so the file I download is a signed apk of a previous version, which I think should work without any issues. 

From the suggestion in: https://stackoverflow.com/questions/19045353/an-existing-package-by-the-same-name-with-a-confilcting-signature-is-already-ins I tried to run the emulator both in debug mode and in normal mode... neither worked. 

Any thoughts on what I&#39;m missing?

  [1]: http://i.stack.imgur.com/tjUz8.jpg

Android App Not Install. An existing package by the same name with a conflicting signature is already installed

    line-height: 1.428571429;

Why does [Bootstrap set `line-height`](http://getbootstrap.com/customize/) to this value?

([Some themes](http://netdna.bootstrapcdn.com/bootswatch/3.1.1/readable/bootstrap.min.css) round it to 1.42857143.)

Why does Bootstrap set the line-height property to 1.428571429?

<pre><code class="hljs language-arduino">line-height: 1.428571429;
</code></pre>
Why does <a href="http://getbootstrap.com/customize/" target="_blank" rel="noopener noreferrer">Bootstrap set <code>line-height</code></a> to this value?
(<a href="http://netdna.bootstrapcdn.com/bootswatch/3.1.1/readable/bootstrap.min.css" target="_blank" rel="noopener noreferrer">Some themes</a> round it to 1.42857143.)

Please explain to me when to use the classes `container` and `row`. I&#39;m not sure because the documentation of Bootstrap is quite unclear about this part.

I&#39;m using Bootstrap 3.

When should I use container and row in Twitter Bootstrap?

I know this has been asked a thousand time but I can&#39;t find a way to make the text and image to be centered vertically.

I&#39;m using Twitter Bootstrap 3 with dynamic content so therefor, I do not know the size on neither the text nor the image. Plus, I want it all to be responsive.

I&#39;ve created a [bootply](http://bootply.com/94381) that summarize the kind of layout I&#39;m trying to achieve. Basically, I want the text and image to be vertically centered. The text is not always bigger than the image.

Can someone help me out with this please?

Thank you.

Twitter Bootstrap 3, vertically center content

Having some trouble with bootstrap, so some help would be awesome. Thanks

What I would like:(top part)

![enter image description here][1]

My current code:

    &lt;div class=&quot;form-group&quot;&gt;
        &lt;input type=&quot;text&quot; 
               class=&quot;form-control&quot; 
               id=&quot;findJobTitle&quot; 
               name=&quot;findJobTitle&quot; 
               placeholder=&quot;Job Title, Keywords&quot; 
               onkeyup=&quot;showResult()&quot;&gt; 
    &lt;/div&gt;

Current Screenshot:

![enter image description here][2]


  [1]: http://i.stack.imgur.com/6jtBr.png
  [2]: http://i.stack.imgur.com/Ljyg5.png

How do I clear a search box with an &#39;x&#39; in bootstrap 3?

How can I create a larger space between each link on my navbar, so they are further apart?
Is it something I change the CSS or HTML?
Here&#39;s how I&#39;ve implemented my navbar in the html:

    &lt;div class=&quot;navbar-wrapper&quot;&gt;
	&lt;div class=&quot;container&quot;&gt;
		&lt;div class=&quot;navbar navbar-static-top&quot; role=&quot;navigation&quot;&gt;
        &lt;div class=&quot;container full-width&quot;&gt;
        &lt;div class=&quot;navbar-header&quot;&gt;
              &lt;button type=&quot;button&quot; class=&quot;navbar-toggle&quot; data-toggle=&quot;collapse&quot; data-target=&quot;.navbar-collapse&quot;&gt;
                &lt;span class=&quot;sr-only&quot;&gt;Toggle navigation&lt;/span&gt;
                &lt;span class=&quot;icon-bar&quot;&gt;&lt;/span&gt;
                &lt;span class=&quot;icon-bar&quot;&gt;&lt;/span&gt;
                &lt;span class=&quot;icon-bar&quot;&gt;&lt;/span&gt;
              &lt;/button&gt;
        	&lt;a class=&quot;navbar-brand&quot; href=&quot;#&quot;&gt;&lt;/a&gt;
         &lt;/div&gt;
         &lt;div class=&quot;navbar-collapse collapse&quot;&gt;
         	&lt;ul class=&quot;nav navbar-nav navbar-right&quot;&gt;
                &lt;li class=&quot;active&quot;&gt;&lt;a href=&quot;#home_page&quot;&gt;Home&lt;/a&gt;&lt;/li&gt;
                &lt;li&gt;&lt;a href=&quot;#about_page&quot;&gt;About&lt;/a&gt;&lt;/li&gt;
                &lt;li&gt;&lt;a href=&quot;#portfolio_page&quot;&gt;Portfolio&lt;/a&gt;&lt;/li&gt;
                &lt;li&gt;&lt;a href=&quot;#contact_page&quot;&gt;Contact&lt;/a&gt;&lt;/li&gt;
            &lt;/ul&gt;
         &lt;/div&gt;
         &lt;/div&gt;
         &lt;/div&gt;
	&lt;/div&gt;
    &lt;/div&gt;

Changing the space between each item in Bootstrap navbar

![position a div at centre of a responsive page][1]


  [1]: http://i.stack.imgur.com/vXdbR.jpg

I need to create a responsive page using bootstrap by position a div at the centre of a page as like in the below mentioned layout.

In a bootstrap responsive page how to center a div

In bootstrap 2 the dropdown menu had an upwards arrow as it can be seen [here][1]
(i am not talking about the carret). Now using bootstrap 3 or latest git this arrow doesn&#39;t exist in my simple example bellow nor in the [examples][2] on the bootstrap homepage.

How can I add this arrow again using bootstrap 3? 

      &lt;li class=&quot;dropdown&quot;&gt;
        &lt;a href=&quot;#&quot; class=&quot;dropdown-toggle&quot; data-toggle=&quot;dropdown&quot;&gt;
          Menu
          &lt;b class=&quot;caret&quot;&gt;&lt;/b&gt;
        &lt;/a&gt;
        &lt;ul class=&quot;dropdown-menu&quot;&gt;
          &lt;li&gt;&lt;a href=&quot;#&quot;&gt;a&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href=&quot;#&quot;&gt;b&lt;/a&gt;&lt;/li&gt;
          &lt;li&gt;&lt;a href=&quot;#&quot;&gt;c&lt;/a&gt;&lt;/li&gt;
        &lt;/ul&gt;
      &lt;/li&gt;

PS:To be precise the picture can be seen in [another][3] stackoverflow article.


  [1]: http://getbootstrap.com/2.3.2/javascript.html#dropdowns
  [2]: http://getbootstrap.com/javascript/#dropdowns
  [3]: https://stackoverflow.com/questions/15792132/bootstrap-remove-upward-arrow-in-dropdown
  [4]: http://i.stack.imgur.com/63dE8.png

bootstrap 3 arrow on dropdown menu

I&#39;m including an SVG image file on my page within an `object` tag, like this:

    &lt;object type=&quot;image/svg+xml&quot; data=&quot;linkto/image.svg&quot;&gt;
       &lt;!-- fallback image in CSS --&gt;
    &lt;/object&gt;

The image in question is a world map, i want to transition the `fill` property when the mouse hovers over a `group`, in this case I&#39;ve grouped my SVG by continent, so South America looks something like this:

    &lt;g id=&quot;south_america&quot;&gt;
	    &lt;path fill=&quot;#FAFAFA&quot; d=&quot;(edited for brevity)&quot;/&gt;
    &lt;/g&gt;

I can get the `fill` property to change on hover by using the following CSS at the top of my SVG document:

    &lt;style&gt;
    #south_america path {
	    transition: fill .4s ease;
	}
	#south_america:hover path {
	    fill:white;
	}
    &lt;/style&gt;

But I can&#39;t get the `fill` colour to fade in with a CSS transition, the colour just changes instantly, can anyone shed light on this please?

Using CSS to transition the fill property of an SVG path on hover

I have a JPEG file that I&#39;m using as a background image for a search page, and I&#39;m using CSS to set it because I&#39;m working within [Backbone.js][1] contexts:

    background-image: url(&quot;whatever.jpg&quot;);

I want to apply a CSS 3 blur filter *only* to the background, but I&#39;m not sure how to style just that one element. If I try:

    -webkit-filter: blur(5px);
    -moz-filter: blur(5px);
    -o-filter: blur(5px);
    -ms-filter: blur(5px);
    filter: blur(5px);

just underneath `background-image` in my CSS, it styles the whole page, rather than just the background. Is there a way to select just the image and apply the filter to that? Alternatively, is there a way to just turn the blur off for every other element on the page?

  [1]: https://en.wikipedia.org/wiki/Backbone.js


How to apply a CSS filter to a background image

My CSS file is in :

Project/Web/Support/Styles/file.css

My image is in :

Project/Web/images/image.png

I want this image in my CSS file.

I have tried :

    1) background-image: url(/images/image.png);
    2) background-image: url(&#39;/images/image.png&#39;);
    3) background-image: url(&quot;/images/image.png&quot;);
    4) background-image: url(../images/image.png);
    5) background-image: url(&#39;../images/image.png&#39;);
    6) background-image: url(&quot;../images/image.png&quot;);

But. i&#39;m not getting this image in my page.

What is the correct way to specify the path of image file in the css file ?

Content Type	Original Author	Original Content on Stackoverflow
Question	Ziyu Zhou	View Question on Stackoverflow
Solution 1 - Twitter Bootstrap	Hynes	View Answer on Stackoverflow

Why does Bootstrap set the line-height property to 1.428571429?

Twitter Bootstrap Problem Overview

Twitter Bootstrap Solutions

Solution 1 - Twitter Bootstrap

Android App Not Install. An existing package by the same name with a conflicting signature is already installed

How can I remove Nan from list Python/NumPy

Attributions