7. EQUITY COMPENSATION PLANS (Details - Option activity)	9 Months Ended
Jan. 31, 2018 $ / shares shares
Number of Options
Number of Options Outstanding, Beginning \| shares	4,081,548
Number of Options Granted \| shares	679,497
Number of Options Exercised \| shares	(117,019)
Number of Options Canceled or Expired \| shares	(654,670)
Number of Options Outstanding, Ending \| shares	3,989,356
Weighted Average Exercise Price
Weighted Average Exercise Price Outstanding, Beginning \| $ / shares	$ 8.77
Weighted Average Exercise Price Granted \| $ / shares	4.17
Weighted Average Exercise Price Exercised \| $ / shares	3.40
Weighted Average Exercise Price Canceled or Expired \| $ / shares	8.42
Weighted Average Exercise Price Outstanding, Ending \| $ / shares	$ 8.70

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)-(4)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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-Publisher FASB
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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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