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Polar coordinates are used mostly for drawing...? Circles Arcs Vertical lines Angled lines

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Question ajoutée par ماحي عابد , Civil engineer , Technical building control
Date de publication: 2015/04/11
Syed Shan Haider
par Syed Shan Haider , Senior Draftsman , Al Marwan General Contracting Company

The Answer is Angled  Lines. About Entering2D Polar Coordinates  

 

You can use absolute or relative polar coordinates (distance and angle) to locate points when creating objects.

To use polar coordinates to specify a point, enter a distance and an angle separated by an angle bracket (<).

By default, angles increase in the counterclockwise direction and decrease in the clockwise direction. To specify a clockwise direction, enter a negative value for the angle. For example, entering 1<315 locates the same point as entering1<-45. You can change the angle conventions for the current drawing with the UNITS command.

Absolute Polar Coordinates

Absolute polar coordinates are measured from the UCS origin (0,0), which is the intersection of the X and Y axes. Use absolute polar coordinates when you know the precise distance and angle coordinates of the point.

With dynamic input, you can specify absolute coordinates with the # prefix. If you enter coordinates on the command line instead of in the tooltip, the # prefix is not used. For example, entering #3<45 specifies a point3 units from the origin at an angle of45 degrees from the X axis.

The following example shows two lines drawn with absolute polar coordinates using the default angle direction setting. Enter the following in the tooltip:

Command: line

From point: #0,0

To point: #4<120

To point: #5<30

Relative Polar Coordinates

Relative coordinates are based on the last point entered. Use relative coordinates when you know the location of a point in relation to the previous point.

To specify relative coordinates, precede the coordinate values with an @ sign. For example, entering @1<45 specifies a point at a distance of1 unit from the last point specified at an angle of45 degrees from the X axis.

The following example shows two lines drawn with relative polar coordinates. In each illustration, the line begins at the location labeled as the previous point.

Command: line

From point: @3<45

To point: @5<285

 

USAMA YOSSRY AHMED GENDIA
par USAMA YOSSRY AHMED GENDIA , Resident Engineer , ACE ARAB CONSULANT ENGINEER - MOHARM BAKHOOM

Polar Coordinates

  Polar coordinates allow you to define a point by specifying the distance and the direction from a given point. This mode of measurement is quite helpful in working with angles. To draw a line at an angle, you need to specify how long a line you want to draw and specify the angle.

The Format to Enter Coordinates

Cartesian or polar coordinate values can be entered in two formats:  

  • Absolute
  • Relative

Absolute format is a way of measuring distances from a fixed reference location (origin point), which is the0,0 location of the coordinate system. Consider this point to be stationary at all times. In some CADD programs this point remains visible at the left bottom corner of the drawing area, while in others it is invisible. You can use this point as a reference to measure any distance in the drawing. Absolute coordinates are primarily used to adjust the alignment of diagrams in a drawing, to align one drawing with another or to make plotting adjustments.

Relative format is a way of measuring distances from the last point entered. All measurements are taken the same way as the absolute coordinates, with the only difference being that the relative coordinates are measured from the last point entered instead of the origin point. When a point is entered, it becomes the reference for entering the next point and so on. This mode of measurement is frequently used for drawing because it is always convenient to place the drawing components relative to each other rather than a fixed reference point.

Note:

Each CADD program uses its own annotations to enter absolute or relative coordinates. The task table located at the end of the chapter shows some examples from leading CADD programs.

A Prototype CADD Drawing

A CADD program is designed to meet the needs of a vast number of individuals. It comes with a number of options that can be customized. For example, architects, engineers and surveyors use different annotations to measure units and to draw dimensions. You may have a number of preferences regarding a specific style of text, standard sheet sizes, names of layers, symbol styles, borders, or line types to be used in a project.

When you install a CADD program, it does not have any of the defaults set as per your requirements. You can create a prototype drawing and specify all the defaults that you would like to use. This prototype drawing acts as a template that can be used for all future projects.

When you start a new drawing, you can specify the name of the prototype drawing and all the defaults are taken from this file. This gives you a drawing of a specified size, with border type and all the other defaults set in the prototype drawing. When you start working with CADD, it is better to follow a prototype drawing. It saves a significant amount of time in starting a drawing, because CADD sets everything for you. You are ready to draw instantly.

Most programs allow you to create more than one prototype drawing and save them under different filenames. This is particularly helpful when you are working on several projects that require different drawing standards. Whenever you need to use a specific standard, you can specify the name of that prototype drawing and those defaults are activated

Elke Woofter
par Elke Woofter , Project Assistant , American Technical Associates

In AutoCAD the polar coordinate system is used to place lines from one point to an other (angled or straight) ... items like circles are set at a coordinate point.

 

Faizan Zakir Malik
par Faizan Zakir Malik , CAD Designer , Royal Commission Yanbu

I agree with Elke Woofter

Correct Answer is angled line

محمد يونس
par محمد يونس , مهندس مشرف , الشركة العامة للكهرباء

USING for  drawing angle line .

Utilisateur supprimé
par Utilisateur supprimé

The polar coordinate system is a two-dimensional mathematical coordinate system that serves as an alternative to the familiar Cartesian coordinate system. In the polar coordinate system, points are referenced from a central origin identical to that of the Cartesian system, point (0,0). Polar points are generally described by the variables "r," representing a radial distance from the origin, and "θ," which represents the angle from an arbitrary axis. Polar equations can be found from a Cartesian equation expressed in terms of "x" and "y."