Navigating and Viewing the Contents

Two main categories available for browsing are Documentation and Model Libraries.

Browsing Documentation
- To start browsing, click on Documentation in the top left area of the page. Use a table of contents on the left hand side of each page to navigate through documentation.
- To display the content of the page, click on a topic entry in the table of contents on the left hand side.
- To either expand or hide all immediate subtopics of the topic, click on the blue arrow next in front of the topic entry.
Browsing Model Libraries
- To start browsing, click on Model Libraries in the top left are of the page and select the model library of interest. Each model Library page lists all available models in a table.
- To select the number of entries to be showed per page, select the number from a drop-down list on the top left of the table.
- To filter the entries currently displaying in the page, type in a keyword into search box on the top right of the table.
- To sort the entries alphabetically in either ascending order or decending order, click on the arrows in a column header of the table.

Use the Back and Forward functions in the browser to navigate the history of viewed topics, and click on Documentation or on Model Libraries to restart browsing topics from the main pages.

Searching for Contents

Searching for Contents come into two different search categories; Searching for Online Contents and Search for Offline Contents. Searching for Online Contents searches for the documents on the website and it is possible to search a number of GAMS document versions that are available on the web site. Search for Offline Contents only searches the document that comes with the installed GAMS distribution and the search is available without network connection requirement. Note that we are using different search engine for offline document and online document. The different search strategies may return different search results.

Regardless of search categories, it is possible to search for contents of both Documentation and Model Libraries. Search is accessible by either entering a search keyword in a search box shown on top of every document page or clicking on the search link embeded in the contents of some pages. Depending on whether the current page is under Documentation or Model Libraries, either the Documentation or the Model Libraries will be searched by default. Though it is possible to later switch between searching documentation and searching model libraries within the search page.

Searching for Online Contents

Searching for online contents search the document on the website and is accessible via online search.

when entering a search keyword in a search box shown on top of every document page, either the Documentation or the Model Libraries will be searched depending on whether the current page is under Documentation or Model Libraries.
Select the search category to switch between search documentation and search model libraries.
Select a tab with a section name to narrow down the search scope.

For GAMS version 28 on, when the search term has a prefix match to the index (See also Browsing Index for Known Keywords), the search result suggests the list of related keywords allow to access the contents directly using the known keyword.

Follows the following search expression rules to search the online contents:

The online search engine ignores character case. For example:
```
GAMS 
```
returns topics that contain gams, Gams, GaMs, and GAMS.
The search engine performs exact keyword search. For example, the keyword:
```
create 
```
returns hits on topics that contain create but not creates, creating, creator, and so on.
The search engine performs wildcard search for single character using ? and multiple characters using *. For example, the keyword:
```
ga? 
```
returns hits on topics that contain gap and gas but not gams.
```
ga* 
```
returns hits on topics that contain gap, gas, gams, gamma, gamsworkspace, and so on.
The search engine implies AND between all search terms. In other words, topics that contain all the search terms will be returned. For example:
```
objective function 
```
returns topics that contain both objective and function, but not necessarily in a successive order. To search for exact words, use double quotation. For example:
```
"objective function" 
```
searches topics that contain both objective and function in a successive order.
The search engine performs boolean search using the following boolean operators: AND, OR, NOT, +, and -. For example:
```
objective AND function 
```
returns topics that contain both objective and function, but does not return topics that contain only one of these words.
```
objective OR function 
```
returns topics that contain either objective or function.
```
objective NOT function 
```
returns topics that contain the word objective but exclude the word function.
```
+objective function 
```
returns topics that must contain the word objective but may contain function.
```
-objective function 
```
returns topics that exclude the word objective but contian the word function.

The following stop words are common English words which will be ignored (not searched for) if they appear in the search expression:

a, able, about, across, after, all, almost, also, am, among, an, and, any, are, as, at, be, because, been, but, by, can, cannot, could,  dear, did, do, does, either, else, ever, every, for, from, get, got, had, has, have, he, her, hers, him, his, how, however, i, if, in, into, is, it, its, just, least, let, like, likely, may, me, might, most, must, my, neither, no, nor, not, of, off, often, on, only, or, other, our, own, rather, said, say, says, she, should, since, so, some, than, that, the, their, them, then, there, these, they, this, tis, to, too, twas, us, wants, was, we, were, what, when, where, which, while, who, whom, why, will, with, would, yet, you, your

Search for Offline Contents

Searching for offline contents searches only the the document that comes with the installed GAMS distribution and is available without network connection requirement.

when entering a search keyword in a search box shown on top of every document page, either the Documentation or the Model Libraries will be searched depending on whether the current page is under Documentation or Model Libraries.
- Select the search category to switch between search documentation and search model libraries.
Select a tab with a section name to narrow down the search scope.

When the search term has a prefx match to the index (See also Browsing Index for Known Keywords), the search result suggests the list of related keywords allow to access the contents directly using the known keyword.

Follows the following search expression rules to search the offline contents:

The search engine ignores character case. For example:
```
GAMS 
```
returns topics that contain gams, Gams, GaMs, and GAMS.
The search engine does "fuzzy" searches and word stemming. If you enter
```
create 
```
it will return hits on topics that contain creates, creating, creator, and so on.
The search engine implies OR between all search terms. In other words, topics that contain either of the search terms will be returned. For example:
```
objective function 
```
returns topics that contain contain either one of these words.
The search engine uses the operators: +, and - to control the term presence of the search results. For example:
```
+objective +function 
```
returns topics that must contain the word objective and function, though not necessarily in sucessive order
```
+objective function 
```
returns topics that must contain the word objective but may contain function.
```
-objective function 
```
returns topics that exclude the word objective but contian the word function.

The following stop words are common English words which will be ignored (not searched for) if they appear in the search expression:

a, able, about, across, after, all, almost, also, am, among, an, and, any, are, as, at, be, because, been, but, by, can, cannot, could,  dear, did, do, does, either, else, ever, every, for, from, get, got, had, has, have, he, her, hers, him, his, how, however, i, if, in, into, is, it, its, just, least, let, like, likely, may, me, might, most, must, my, neither, no, nor, not, of, off, often, on, only, or, other, our, own, rather, said, say, says, she, should, since, so, some, than, that, the, their, them, then, there, these, they, this, tis, to, too, twas, us, wants, was, we, were, what, when, where, which, while, who, whom, why, will, with, would, yet, you, your

To search within one document page for a specific word or phrase, use Find... (for example, CTRL+F) function in the browser.

Browsing Index for Known Keywords

The Index page provides a convenient way to access specific locations in the documentation through a list of interesting keywords. Note that only GAMS Documentation pages are indexed and not all sections contain an index, e.g., there is no index for model libraries.

To browse Index page for known keywords:

Click on Index on the top right area of each document page to start browsing index.
Type in a keyword into a keyword box to match the prefix of all keywords in the list.
Check case sensitive box to do case sensitive filtering or check Match whole word box to match the whole word.

Reloading page in a Printer-Friendly Format

Clicking on a printer-friendly verion at the bottom left of the page to reload the contents of the same page without the table of contents for navigation.

It is also possible to append a string after the url of the page in the browser navigation bar and use the browser reload function. The string is one of the followings:

?print=1 - get the page contents without styles and without the table of contents for navigation
?print=2 - get the page contents with styles but without the table of contents for navigation

Conventions for GAMS Syntax Representation

The syntax used to introduce features in the various chapters are presented using a format inspired by the Backus-Naur form (BNF) notation where:

Notation	Description
`[]`	the enclosed construct is optional
`{}`	the enclosed construct may be repeated zero or more times
`¦`	there is an or operator across the arguments on both sides of the symbol

Table of Contents