10.49.2 Greatest hits from previous weeks

10.49.2.1 \mathbb Z  yields undefined control sequence error
10.49.2.2 Force figure placement in text
10.49.2.3 Error in TeX Live a^\200\223 Font ... not loadable: Metric (TFM) file not found
10.49.2.4 How to write two dot above a letter?
10.49.2.5 How to write partial differential equation (Ex. dQ/dt=ds/dt) with real partial derivative signs?
10.49.2.6 How to change certain pages into landscape/portrait mode
10.49.2.7 How can I get bold math symbols?
10.49.2.1 \mathbb Z  yields undefined control sequence error

https://tex.stackexchange.com/landing/r/digest?cta=question&id=38769

I am using WinEdt 6 for compiling my TeX documents. I am getting an error with contains the line $\mathbb{Z}$ showing that it is undefined control sequence. How should I rectify it? Should I include ... 
[math-mode] [errors] [symbols]
 
asked by Ramana Venkata https://tex.stackexchange.com/landing/r/digest?cta=user&id=10154 Score of 253
answered by TorbjA~,rn T. https://tex.stackexchange.com/landing/r/digest?cta=user&id=586 Score of 312
10.49.2.2 Force figure placement in text

https://tex.stackexchange.com/landing/r/digest?cta=question&id=8625

I have a problem when a lot of figures are in question. Some figures tend to "fly around", that is, be a paragraph below, although I placed them before that paragraph. I use code: 
\begin{figure}[ht] 
\... 
[floats] [positioning] [captions]
 
asked by Marin https://tex.stackexchange.com/landing/r/digest?cta=user&id=2755 Score of 679
answered by Juan A. Navarro https://tex.stackexchange.com/landing/r/digest?cta=user&id=169 Score of 830
10.49.2.3 Error in TeX Live a^\200\223 Font ... not loadable: Metric (TFM) file not found

https://tex.stackexchange.com/landing/r/digest?cta=question&id=75166

I freshly installed 'basic' version of TeX Live 2012 (not full, only basic version). 
I have following line in my code: 
\usepackage[T1]{fontenc} 
I get following error: 
(/usr/local/texlive/2012/texmf-... 
[fonts] [errors] [packages] [texlive] [font-encodings]
 
asked by abhinavkulkarni https://tex.stackexchange.com/landing/r/digest?cta=user&id=12992 Score of 155
10.49.2.4 How to write two dot above a letter?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=152951

the two dots above a letter represents two derivative of varible t. 
My method: 
\documentclass[UTF8]{ctexart} 
\usepackage{amsmath} 
\usepackage{amssymb} 
\usepackage{graphicx} 
\usepackage{epstopdf} 
\... 
[math-mode] [accents]
 
asked by mma https://tex.stackexchange.com/landing/r/digest?cta=user&id=43727 Score of 148
answered by Cain https://tex.stackexchange.com/landing/r/digest?cta=user&id=28428 Score of 201
10.49.2.5 How to write partial differential equation (Ex. dQ/dt=ds/dt) with real partial derivative signs?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=225523

I would like to make a partial differential equation by using the following notation: 
dQ/dt 
(without / but with a real numerator and denomenator). Earlier today I got help from this page on how to ... 
[equations]
 
asked by David https://tex.stackexchange.com/landing/r/digest?cta=user&id=71265 Score of 142
answered by Sebastiano https://tex.stackexchange.com/landing/r/digest?cta=user&id=117876 Score of 18
10.49.2.6 How to change certain pages into landscape/portrait mode

https://tex.stackexchange.com/landing/r/digest?cta=question&id=337

How can I change the orientation of some pages of my document into landscape mode, while leaving the others in portrait mode (or vice versa)? 
[landscape]
 
asked by hayalci https://tex.stackexchange.com/landing/r/digest?cta=user&id=183 Score of 455
answered by rcs https://tex.stackexchange.com/landing/r/digest?cta=user&id=118 Score of 471
10.49.2.7 How can I get bold math symbols?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=595

To make Latin-letter variables bold I can use e.g. \mathbf{a}, but while putting Greek letters or symbols such as \nabla inside \mathbf doesn't cause any errors or warnings, it also doesn't do ... 
[fonts] [math-mode] [symbols] [bold]
 
asked by Michael Underwood https://tex.stackexchange.com/landing/r/digest?cta=user&id=32 Score of 642
answered by Mark Meckes https://tex.stackexchange.com/landing/r/digest?cta=user&id=206 Score of 549