Arithmetic progression

[XML] [Smart Pascal] [JavaScript] [Python] [output]

This demonstration outputs the last term and arithmetic series (sum) of an arithmetic progression given the first term, difference and number of terms. It shows how arithmetic can be built up from several blocks in a chain.

We used the Blockly Playground to generate the JavaScript and Python code from the same blocks.

The blocks

The blocks

XML Code of Blocks

<xml xmlns="http://www.w3.org/1999/xhtml">
  <block type="procedures_defnoreturn" id="f6Ob)+^iHN_}K;WTlfaH" x="13" y="113">
    <mutation>
      <arg name="floatFirst"></arg>
      <arg name="floatDifference"></arg>
      <arg name="intTerms"></arg>
    </mutation>
    <field name="NAME">SeqA</field>
    <comment pinned="false" h="80" w="160">Outputs last term and series of arithmetic progression
with first term floatFirst, difference floatDifference
and number of terms intTerms
    </comment>
    <statement name="STACK">
      <block type="variables_set" id=":wlgM#^Z}DR.rHBszgue">
        <field name="VAR">floatLast</field>
        <value name="VALUE">
          <block type="math_arithmetic" id="ZWP;Z:)=`BIi3Crt7DnQ">
            <field name="OP">ADD</field>
            <value name="A">
              <shadow id="(2c=X2`*Wy$}}Ai~8*,8" type="math_number">
                <field name="NUM">1</field>
              </shadow>
              <block type="variables_get" id="93w;iJfG%X)ExL=xKZPY">
                <field name="VAR">floatFirst</field>
              </block>
            </value>
            <value name="B">
              <shadow id="T2eL{c2O;i,FUa7|Kbxr" type="math_number">
                <field name="NUM">1</field>
              </shadow>
              <block type="math_arithmetic" id="wH#_OBn7M~@@7yRco`i_">
                <field name="OP">MULTIPLY</field>
                <value name="A">
                  <shadow id="I.?I[u*fSuwu8.-k70Xh" type="math_number">
                    <field name="NUM">1</field>
                  </shadow>
                  <block type="variables_get" id="4Aqb(DR?:c6wYW:JMP_l">
                    <field name="VAR">floatDifference</field>
                  </block>
                </value>
                <value name="B">
                  <shadow id="E%]$1$6tfK6)Hiw2_=E[" type="math_number">
                    <field name="NUM">1</field>
                  </shadow>
                  <block type="math_arithmetic" id="$y?/5UX7!_S-VpbdvL{X">
                    <field name="OP">MINUS</field>
                    <value name="A">
                      <shadow id="=05q#J+aTs[T0b$_L4L+" type="math_number">
                        <field name="NUM">1</field>
                      </shadow>
                      <block type="variables_get" id="cAzuk~pW?aNAOKGIrr@]">
                        <field name="VAR">intTerms</field>
                      </block>
                    </value>
                    <value name="B">
                      <shadow type="math_number" id="qPZuJ9-U3)k!+00/i!wT">
                        <field name="NUM">1</field>
                      </shadow>
                    </value>
                  </block>
                </value>
              </block>
            </value>
          </block>
        </value>
        <next>
          <block type="variables_set" id="}:#Xq_FxT)|6y*zz1kd{">
            <field name="VAR">floatSeries</field>
            <value name="VALUE">
              <block type="math_arithmetic" id="v1fNU$+jO[,(cYtC89a]">
                <field name="OP">DIVIDE</field>
                <value name="A">
                  <shadow id="UjuUT~EF_p(36$W.]a8S" type="math_number">
                    <field name="NUM">1</field>
                  </shadow>
                  <block type="math_arithmetic" id="3bWz19at(bM*;$D{,VM{">
                    <field name="OP">MULTIPLY</field>
                    <value name="A">
                      <shadow id="({kR#AHOV#[*WT8Gl$2#" type="math_number">
                        <field name="NUM">1</field>
                      </shadow>
                      <block type="variables_get" id="_f]w9h/7uB[DX/XpD/9W">
                        <field name="VAR">intTerms</field>
                      </block>
                    </value>
                    <value name="B">
                      <shadow id="{^VWVQtJJ,;DtAeF:ua5" type="math_number">
                        <field name="NUM">1</field>
                      </shadow>
                      <block type="math_arithmetic" id="B/lY%;iC]NB@*?|yf1oZ">
                        <field name="OP">ADD</field>
                        <value name="A">
                          <shadow id="(2c=X2`*Wy$}}Ai~8*,8" type="math_number">
                            <field name="NUM">1</field>
                          </shadow>
                          <block type="math_arithmetic" id="dZ2[N$3:(l62#(]S;J.A">
                            <field name="OP">MULTIPLY</field>
                            <value name="A">
                              <shadow type="math_number" id=":mHx$i/E6wL$Ve%tVVq^">
                                <field name="NUM">2</field>
                              </shadow>
                            </value>
                            <value name="B">
                              <shadow id="gNz_rreMM,.qW[.!gBep" type="math_number">
                                <field name="NUM">1</field>
                              </shadow>
                              <block type="variables_get" id="MTuaB~:RPdKN1(=Y91fB">
                                <field name="VAR">floatFirst</field>
                              </block>
                            </value>
                          </block>
                        </value>
                        <value name="B">
                          <shadow id="T2eL{c2O;i,FUa7|Kbxr" type="math_number">
                            <field name="NUM">1</field>
                          </shadow>
                          <block type="math_arithmetic" id="MUqY5BPI;B,,uen`}lDK">
                            <field name="OP">MULTIPLY</field>
                            <value name="A">
                              <shadow id="I.?I[u*fSuwu8.-k70Xh" type="math_number">
                                <field name="NUM">1</field>
                              </shadow>
                              <block type="variables_get" id="-Hf8VbFj0b8peKGMV8wj">
                                <field name="VAR">floatDifference</field>
                              </block>
                            </value>
                            <value name="B">
                              <shadow id="E%]$1$6tfK6)Hiw2_=E[" type="math_number">
                                <field name="NUM">1</field>
                              </shadow>
                              <block type="math_arithmetic" id="zy@y#frN:V.zTS];ye[d">
                                <field name="OP">MINUS</field>
                                <value name="A">
                                  <shadow id="=05q#J+aTs[T0b$_L4L+" type="math_number">
                                    <field name="NUM">1</field>
                                  </shadow>
                                  <block type="variables_get" id="B2=CE.ms^?b3D8dG2H1{">
                                    <field name="VAR">intTerms</field>
                                  </block>
                                </value>
                                <value name="B">
                                  <shadow type="math_number" id="CGKi{D)7t;cAVp,vO9XY">
                                    <field name="NUM">1</field>
                                  </shadow>
                                </value>
                              </block>
                            </value>
                          </block>
                        </value>
                      </block>
                    </value>
                  </block>
                </value>
                <value name="B">
                  <shadow type="math_number" id="2]tc4y6eAfSzd~}d090|">
                    <field name="NUM">2</field>
                  </shadow>
                </value>
              </block>
            </value>
            <next>
              <block type="text_print" id="76`i3m%!k$/pUySvo*1#">
                <value name="TEXT">
                  <shadow id="`m5bGJ@-w/+(?eaYWUC?" type="text">
                    <field name="TEXT">abc</field>
                  </shadow>
                  <block type="text_join" id="6hqAv![$6ILgF_j4U00j">
                    <mutation items="4"></mutation>
                    <value name="ADD0">
                      <block type="text" id="exn`,EvF*rERF_hQ,(Eh">
                        <field name="TEXT">Last term: </field>
                      </block>
                    </value>
                    <value name="ADD1">
                      <block type="variables_get" id="um$BgIKhAj84;4gUQqIE">
                        <field name="VAR">floatLast</field>
                      </block>
                    </value>
                    <value name="ADD2">
                      <block type="text" id="Ih7k1DC{.(i9{*iPOy35">
                        <field name="TEXT"> Series (sum): </field>
                      </block>
                    </value>
                    <value name="ADD3">
                      <block type="variables_get" id="Vn$cf[(wRZ;6bZ-L6[P2">
                        <field name="VAR">floatSeries</field>
                      </block>
                    </value>
                  </block>
                </value>
              </block>
            </next>
          </block>
        </next>
      </block>
    </statement>
  </block>
  <block type="variables_set" id="#t#Fc,)qcSM4Av@go]TH" x="12" y="413">
    <field name="VAR">floatFirst</field>
    <value name="VALUE">
      <block type="text_prompt_ext" id="L_$41vMwhIrk=(Z_mimP">
        <mutation type="NUMBER"></mutation>
        <field name="TYPE">NUMBER</field>
        <value name="TEXT">
          <shadow type="text" id="Ni|`H*mNW-w{Ri]lOKvB">
            <field name="TEXT">Please enter first term</field>
          </shadow>
        </value>
      </block>
    </value>
    <next>
      <block type="variables_set" id=".(!d#7ApmSl|!x$Gr_fp">
        <field name="VAR">floatDifference</field>
        <value name="VALUE">
          <block type="text_prompt_ext" id="?qX1ItfuI?tM#!s=PEEi">
            <mutation type="NUMBER"></mutation>
            <field name="TYPE">NUMBER</field>
            <value name="TEXT">
              <shadow type="text" id="Swd:FnirR-FgN;|Tk7S:">
                <field name="TEXT">Please enter difference</field>
              </shadow>
            </value>
          </block>
        </value>
        <next>
          <block type="variables_set" id="sap8n;Xv($FGvjY^oIvc">
            <field name="VAR">intTerms</field>
            <value name="VALUE">
              <block type="math_round" id="X-2^]y[*vZw!R|bJ#t}]">
                <field name="OP">ROUND</field>
                <value name="NUM">
                  <shadow id="or.LKCH_q@nQo_WjdrN}" type="math_number">
                    <field name="NUM">3.1</field>
                  </shadow>
                  <block type="text_prompt_ext" id="nIRgX.M5$D0,FK4YV)~2">
                    <mutation type="NUMBER"></mutation>
                    <field name="TYPE">NUMBER</field>
                    <value name="TEXT">
                      <shadow type="text" id="X(0^8kF[XUBd$c_Mnqd}">
                        <field name="TEXT">Please enter number of terms</field>
                      </shadow>
                    </value>
                  </block>
                </value>
              </block>
            </value>
            <next>
              <block type="procedures_callnoreturn" id=":IR#oM|!]Uh@Ww+07?5/">
                <mutation name="SeqA">
                  <arg name="floatFirst"></arg>
                  <arg name="floatDifference"></arg>
                  <arg name="intTerms"></arg>
                </mutation>
                <value name="ARG0">
                  <block type="variables_get" id=":sJVgYxx@F0ubbpOU2z$">
                    <field name="VAR">floatFirst</field>
                  </block>
                </value>
                <value name="ARG1">
                  <block type="variables_get" id="dWkYH]Cc:Vy|M%~@6^Rf">
                    <field name="VAR">floatDifference</field>
                  </block>
                </value>
                <value name="ARG2">
                  <block type="variables_get" id="1)c$.N?^4izrALE4[av/">
                    <field name="VAR">intTerms</field>
                  </block>
                </value>
              </block>
            </next>
          </block>
        </next>
      </block>
    </next>
  </block>
</xml>

Generated Smart Pascal Code

var floatSeries: Float;
var floatLast: Float;
var intTerms: Integer;
var floatDifference: Float;
var floatFirst: Float;


function Str(v: Variant) : string;
begin
  asm
    if (@v === 0) {
      @Result = '0';
    }
    else if (@v === '') {
      @Result = '';
    }
    else if (isNaN(@v)) {
      @Result = @v;
    }
    else {
      @Result = (@v).toString();
    }
  end;
end;


{
  Outputs last term and series of arithmetic progression
  with first term floatFirst, difference floatDifference
  and number of terms intTerms
}
procedure SeqA(floatFirst: Float; floatDifference: Float; intTerms: Integer);
begin
  floatLast := floatFirst + floatDifference * (intTerms - 1);
  floatSeries := (intTerms * (2 * floatFirst + floatDifference * (intTerms - 1))) / 2;
  Console.writeln(StrJoin([Str('Last term: '), Str(floatLast), Str(' Series (sum): '), Str(floatSeries)],''));
end;



floatFirst := StrToFloat(prompt('Please enter first term'));
floatDifference := StrToFloat(prompt('Please enter difference'));
intTerms := Round(StrToFloat(prompt('Please enter number of terms')));
SeqA(floatFirst, floatDifference, intTerms);

Generated JavaScript

var floatSeries, floatLast, intTerms, floatDifference, floatFirst;

/**
 * Outputs last term and series of arithmetic progression
 * with first term floatFirst, difference floatDifference
 * and number of terms intTerms
 */
function SeqA(floatFirst, floatDifference, intTerms) {
  floatLast = floatFirst + floatDifference * (intTerms - 1);
  floatSeries = (intTerms * (2 * floatFirst + floatDifference * (intTerms - 1))) / 2;
  window.alert(['Last term: ',floatLast,' Series (sum): ',floatSeries].join(''));
}


floatFirst = parseFloat(window.prompt('Please enter first term'));
floatDifference = parseFloat(window.prompt('Please enter difference'));
intTerms = Math.round(parseFloat(window.prompt('Please enter number of terms')));
SeqA(floatFirst, floatDifference, intTerms);

Generated Python Code

import math

floatSeries = None
floatLast = None
intTerms = None
floatDifference = None
floatFirst = None

"""Outputs last term and series of arithmetic progression
with first term floatFirst, difference floatDifference
and number of terms intTerms
"""
def SeqA(floatFirst, floatDifference, intTerms):
  global floatSeries, floatLast
  floatLast = floatFirst + floatDifference * (intTerms - 1)
  floatSeries = (intTerms * (2 * floatFirst + floatDifference * (intTerms - 1))) / 2
  print(''.join([str(x) for x in ['Last term: ', floatLast, ' Series (sum): ', floatSeries]]))

def text_prompt(msg):
  try:
    return raw_input(msg)
  except NameError:
    return input(msg)


floatFirst = float(text_prompt('Please enter first term'))
floatDifference = float(text_prompt('Please enter difference'))
intTerms = round(float(text_prompt('Please enter number of terms')))
SeqA(floatFirst, floatDifference, intTerms)

Copy of Output

The output on entering the values of 1.6 for the first term, 2.6 for the difference and 4 for the number of steps was as follows.

Last term: 9.4 Series (sum): 22
PrevGreen03.png
NextGreen03.png
UpGreen03.png
Programming - a skill for life!

XML, images and generated Smart Pascal code of examples including loops, arrays, validation and recursion

  1. Demonstration of loops
    Simple programs that output the 75 times table and input words from the user
  2. Searching an array
    How to perform a linear search of an array using Blockly
  3. Converting strings to integers
    XML, image and generated Smart Pascal code of demonstration of converting strings to integers
  4. Rounding floats
    How to round a float to a given number of decimal places
  5. Sum, maximum and minimum of arrays
    Example showing the use of the list functions sum, min and max
  6. Subarrays, combining arrays, array sorting and converting arrays to text
    How to copy a subarray from an array, combine arrays, sort an array and convert an array to text
  7. Parallel Arrays
    XML, image and generated Smart Pascal, JavaScript, Python and PHP code of demonstration of parallel arrays
  8. Arithmetic progression
    XML, image and generated Smart Pascal, JavaScript and Python code of demonstration of arithmetic progression
  9. Geometric progression
    XML, image and generated Smart Pascal, JavaScript and Python code of demonstration of geometric progression
  10. Vowel Count
    XML, image and generated Smart Pascal, JavaScript and Python code of demonstration of counting vowels in a word by two methods
  11. Validation using Blockly
    Introduction to validation (length check, range check, presence check, type check and character check)
  12. Recursion and its use for calculating factorials
    XML, image and generated Smart Pascal, JavaScript and Python code of demonstration of recursion for calculating factorials required for the display of Pascal's triangle
  13. Formatting the output with HTML and inline CSS
    XML, image and generated Smart Pascal code of demonstration of use of HTML and CSS
  14. Drawing on a Canvas
    XML, image and generated Smart Pascal code of demonstration of drawing on a canvas
  15. Using the random integer block to create a random identifier
    How to use the random integer block to create a random string for use as an identifier
  16. Generating Smart Pascal code that outputs XML code for a block
    A Blockly example that generates Smart Pascal code to output the XML representation of a block containing an array of numbers entered by the user as a comma-separated list
dita powered logo dita powered™. Copyright © 2010-18 Pascal Programming for Schools. All rights reserved.