Re: [shell-script] Re: Calculando equação do 2 grau

[Julio C. Neves]

Dando uma enxugada rápida, sem testar, fiz assim:

===========================================

#!/bin/bash

clear

echo "

##############################################

######### Cálculo de uma equação #############

############ do segundo grau #################

##############################################"

echo "A equação do 2º grau é da forma ax2 + bx + c."

read -p "Informe o valor de a: " a

read -p "Informe b: " b

read -p "Informe c: " c

let Delta=b**2-4*a*c

((Delta < 0)) && {

        echo "##############################################"

        echo "Delta vale: $Delta "

        echo "Valores inválidos."

        echo "Não posso extrair raiz quadrada de número negativo." >&2

        echo "##############################################"

        exit 1

}

x1=$(bc <<< "scale=2; ($b*-1+sqrt($Delta))/(2*$a)")

x2=$(bc <<< "scale=2; ($b*-1-sqrt($Delta))/(2*$a)")

((Delta == 0)) && echo "As raízes são iguais"

echo "##############################################"

echo "Delta vale: $Delta "

echo -e "x1=$x1\nx2=$x2"

echo "V={$x1;$x2}"

echo "##############################################"

===========================================

Eu já mateium pouco desse echo, echo, echo, ... isso é coisa de marreco! ;) Se quiser melhorar, veja como funciona o printf no Papo de Botequim autentico.

Abcs,

Julio

@juliobash

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Em 31 de maio de 2014 19:39, address@hidden [shell-script] <address@hidden> escreveu:

 

Olá Julio!

Eu intuí que fosse esse o raciocínio...

Tentei colocar em prática a sua sugestão mas não funcionou...

Veja o código e, por gentileza, diga onde estou errando.

#!/bin/bash

echo "##############################################"

echo "######### Cálculo de uma equação #############"

echo "############ do segundo grau #################"

echo "##############################################"

echo "A equação do 2º grau é da forma ax2 + bx + c." 

read -p "Informe o valor de a: " a

read -p "Informe b: " b

read -p "Informe c: " c

let Delta=b**2-4*a*c

((Delta < 0)) && {

    echo "##############################################"

echo "Delta vale: $Delta "

echo "Valores inválidos." 

echo "Não posso extrair raiz quadrada de número negativo." >&2

echo "##############################################"

    exit 1

    }

x=$(bc <<< "scale=2; (($b*-1)/(2*$a)")

x1=$(bc <<< "scale=2; ($b*-1+sqrt($Delta))/(2*$a)")

x2=$(bc <<< "scale=2; ($b*-1-sqrt($Delta))/(2*$a)")

((Delta == 0)) && {

echo "##############################################"

echo "Delta vale: $Delta "

echo "As raízes são iguais"

echo -e "x=$x"

echo "V={$x;$x}"

echo "##############################################"

      exit 1

     }

x1=$(bc <<< "scale=2; ($b*-1+sqrt($Delta))/(2*$a)")

x2=$(bc <<< "scale=2; ($b*-1-sqrt($Delta))/(2*$a)")

echo "##############################################"

echo "Delta vale: $Delta "

echo -e "x1=$x1\nx2=$x2"

echo "V={$x1;$x2}"

echo "##############################################"

Veja a saída.

##############################################

######### Cálculo de uma equação #############

############ do segundo grau #################

##############################################

A equação do 2º grau é da forma ax2 + bx + c.

Informe o valor de a: 1

Informe b: 4

Informe c: 4

(standard_in) 2: syntax error

##############################################

Delta vale: 0 

As raízes são iguais

x=

V={;}

############################################## 

 

Mais uma vez, agradeço a sua atenção.