Wednesday, 21 August 2019

What is Cartography | Firoz Ahmed GIS| VIPC Group

Cartography, the art and science of graphically representing a geographical area, usually on a flat surface such as a map or chart. It may involve the superimposition of political, cultural, or other nongeographical divisions onto the representation of a geographical area.

Types of Map | Firoz Ahmed GIS | VIPC Group


1. Political Map
  • A political map shows the state and national boundaries of a place. A political map does not have any topographic features.
  • It also shows the location of cities, with respect to each other.
2. Physical Map
  • A physical map is one which shows the physical features of a place or country, like rivers, mountains, forests and lakes.
  • The physical features are usually shown in different colors.
  • Rivers and lakes are shown in blue, places of low elevation are shown in dark green and as the elevation increases, the color becomes light green and eventually orange.
  • Mountains are shown in brown.
3. Topographic Map
  • Topographic maps are similar to physical maps, which show the physical features of an area. Although in topographic maps, differences in elevation and changes in landscape are shown with the help of contour lines and not colors.
4. Climatic Map
  • A climatic map shows the information about the climate of different areas.
    For example it shows areas which receive more rainfall or snow, or which have dry weather.
  • It uses colors to depict areas with different climate.
5. Economic or Resource Map
  • Economic or resource maps show the different resources present in the area or economic activity prevalent.
  • They show the kind of crops that are grown and the minerals found in places.
  • Symbols and letters are used to depict the activity or resource present in the area.
6. Road Map
  • Road map is the most widely used map which shows different roads, highways or railways present in the area.
  • It is a very detailed map and is generally used for direction purposes.
  • Road maps are usually made individually, city-wise.
  • There are road maps present for an entire country too, but they cannot be made very detailed.

Introduction to Stack in C language implementing array | Mohd Hasan | VI...

Thursday, 15 August 2019

Wednesday, 14 August 2019

Wall map printing or Large Scale Mapping Layout in ArcGIS


Today we will show you how to do scale based mapping  or how to make wall maps in ArcMap layout

1.First open the arcmap 

       2.Add data (Picture 1)
 Picture 1. Add Data
Note my current scale is 1:19,457,501(Picture 2). So see I will go in layout mode, as you can see in picture 3 that map extent is fit to the current layout, but if I increase the scale from current extent (see picture 4 ,4.1 and 4.2), so map does not fit with layout page.





Picture 2. Scale 1:19,457,501




      Picture 3. Map fit with layout (Here little difference in scale from 1:19,457,501 because we came in layout view from data view)
Picture 4. Changing the scale to 1:10,000,000







Picture 4.1: Map does not fit with current layout (Scale  1:10,000,000)

Picture 4.2: Map does not fit with layout (scale 1:1,000,000)


So question raises that how can we fit 1:10,000,000 or another e.g. 1:1,000,000 scale map with our layout, and we have reduced the scale.

We have seen that if we zoom or reduce scale size so map does not fit with our layout and we are not able to get full extent map at our desired scale.

This problem is very easy to solve we need not to worry about it just
-Change the layout or change the size of page.
·        Open the layout toolbar (See picture 5)

                                Picture 5. Open Layout toolbar
·        Go to change layout (See picture 6

             Picture 7. Change Layout
·        Choose the page size.We are making a small scale map or wall map so in that case we will need to increase our page size because our map is also increasing. I have chosen A 1 page size for our map. (See picture 7)
      Picture 7. Choosing page size
So as you can see in picture 8 that  1:10,000,000 scale map is now fit with our map layout.

                            Picture 8. Full extent map at our desired scale.





You can choose scale according to your need, but remember if you will reduce the scale (zoom the map ) so you will have to also increase the size of page also, otherwise map will not fit with your layout and you will not be able to get your entire map.

Note- I (Firoz Ahmed)  written this tutorial/post for VIPC group. Soon practical video will be uploaded on youtube. If you have any queries, questions or you wants to give any feedback mail to VIPC Group at vipcgroup@gmail.com .

#gis #ArcMap #wallmaps #Layout #Largescalemaps #ArcGIS #ArcGISLayout #Largescalemaps
#esri



Tuesday, 13 August 2019

Introduction to Stack


Stack is an abstract data type with a predefined capacity. It is a linear data structure where we can store same type of Data in a particular order on which some operations are be performed.



Features of Stack
  1. Stack is an ordered list of similar data type.
  2. Stack is a LIFO(Last in First out) structure or we can say FILO(First in Last out).
  3. push() function is used to insert new elements into the Stack and pop() function is used to remove an element from the stack. Both insertion and removal are allowed at only one end of Stack called Top(when stack is empty top is -1).
  4. Stack is said to be in Overflow state when it is completely full and is said to be in Underflow state if it is completely empty.
When do we use stack?
Let’s take an Example of real life application which we often use in our daily life.
In MS-office we often use “BackSpace” key which deletes recent (push() deleted word into stack) word and when we press  “Ctrl+Z” it returns (pop() top of stack ) our deleted words.
Another application of a stack is to reverse a word. You push a given word to stack - letter by letter - and then pop letters from the stack.
There are other uses also like:
  1. Parsing
  2. Expression Conversion(Infix to Postfix, Postfix to Prefix etc)

Implementation of Stack

Stack can be easily implemented using an Array or a Linked List. Arrays are quick, but are limited in size and Linked List requires overhead to allocate, link, unlink, and deallocate, but is not limited in size. Here we will implement Stack using array.

Algorithm for PUSH operation

  • Check if the stack is full or not.
  • If the stack is full, then print error of overflow and exit the program.
  • If the stack is not full, then increment the top and add the element.

code for push operation



Algorithm for POP operation

·        Checks if the stack is empty.
·        If the stack is empty, produces an error and exit.
·        If the stack is not empty, accesses the data element at which top is pointing.
·        Decreases the value of top by 1.
·        Returns success.

code for pop operation



TOP of Stack
It is the recent element of Stack. in starting top is -1 and keeps on increasing when push() function is called until reaches the maximum limit and when pop() function is called it gets decreased until top is not equal to -1.

Algorithm for isEmpty() function
It returns True if Stack is empty else return False Or we can say returns true if top of stack is -1.


code for isEmpty() function


Algorithm for isFull() function
Returns true if top of Stack is equal to the size of defined of Stack (Array).


code for isFull() function




to check running of this program click here

Monday, 12 August 2019

Introduction to Map



What is a map ?
A map is the representation of the surface of earth as a whole or a part of the earth, with convectional signs, drawn to a scale and projection so that each and every point on it correspond to the actual position of the earth.

Elements of a Map
There are the elements of a map (figure_)
i)                Scale
ii)              Title
iii)             Legend
iv)             Projection
v)              North Arrow

Scale: Scale is representation of the two points on the earth and same as on map. We all knows that we cant represent earth’s features with their actual size that’s why reduction is necessary to display features of earth.
Scale is ratio of distance on a map over the corresponding distance on the ground. Map scale is also relation between the dimensions of a map and the dimensions of the earth.
Title: Title of map indicates the purpose of map. Without having title on map we cant know that for what kind of map is this or what is the purpose of map and what is shown over the map.
Legend: Through legend of map we came to know that what features are shown over the map and which symbol is used for which purpose.

figure i :- Map Elements
Projection: Map projection is a systematic drawing of latitude and longitude on a plane surface for the for the whole earth or a part of it on a scale so that any point on the earth surface may correspond to that on the drawing. In other words, map projection is system to project 3 dimensional earth surface to 2 dimensional plane paper drawn on certain scale, and applied some mathematical formulas so that distortions can be removed from the projected area.
North Arrow: North  arrow depicts North direction of map. It is always in UP direction. Knowing the North of arrow helps to understand other geographical direction.

Sunday, 11 August 2019

Introduction to GIS


GIS stands for Geographical Information System. It is defined as an integrated tool, capable of mapping, analyzing, manipulating and storing geographical data in order to provide solutions to real world problems and help in planning for the future. GIS deals with what and where components of occurrences. For example, to regulate rapid transportation, government decides to build fly-over (what component) in those areas of the city where traffic jams are common (where component).
GIS means differently to different people and therefore has different definitions. For example, Burrough (1998) defined GIS as “ a powerful set of tools for collecting, storing, retrieving at will, transforming and displaying spatial data from the real world for a particular set of purposes”
Objectives of GIS
Some of the major objectives of GIS are to
  • Maximizing the efficiency of planning and decision making
  • Integrating information from multiple sources
  • Facilitating complex querying and analysis
  • Eliminating redundant data and minimizing duplication
Components of a GIS
A GIS has following components:
Hardware : It consists of the equipments and support devices that are required to capture, store process and visualize the geographic information. These include computer with hard disk, digitizers, scanners, printers and plottersetc.
Software : Software is at the heart of a GIS system. The GIS software must have the basic capabilities of data input, storage, transfosrmation, analysis and providing desired outputs. The interfaces could be different for different softwares. The GIS softwares being used today belong to either of the category –proprietary or open source. ArcGIS by ESRI is the widely used proprietary GIS software. Others in the same category are MapInfo, Microstation, Geomedia etc. The development of open source GIS has provided us with freely available desktop GIS such as Quantum, uDIG, GRASS, MapWindow GIS etc., GIS softwares.
Data : The data is captured or collected from various sources (such as maps, field observations, photography, satellite imagery etc) and is processed for analysis and presentation.
ProceduresThese include the methods or ways by which data has to be input in the system, retrieved, processed, transformed and presented.
People This component of GIS includes all those individuals (such as programmer, database manager, GIS researcher etc.) who are making the GIS work, and also the individuals who are at the user end using the GIS services, applications and tools.